Electronic device

An electronic apparatus including a housing having an air outlet and a heat generating component in the housing, a heat sink in the housing and having heat radiating fins arrayed. The apparatus includes heat radiating fins having air flow paths between adjacent pairs of the heat radiating fins, and a fan in the housing. The fan feeds air to an air inlet of the heat sink to exhaust heat of the heat radiating fins from the air outlet of the housing. The air outlet of the housing has openings arrayed which divide the air flow paths formed between the pairs of heat radiating fins.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to and claims priority to Japanese Patent Application No. 2007-173353 filed on Jun. 29, 2007 in the Japan Paten Office, the entire contents of which are incorporated herein by reference.

BACKGROUND

The embodiments discussed herein are related to electronic devices. There are demands with electronic devices such as personal computers for even faster processing speed and greater variety of functions equipped. In order to meet such demands, electronic components in an electronic device have increasingly high performance and high density resulting in an increase of heat generated in the electronic device. Heat accumulated in an electronic device may cause a problem of deterioration of the electronic components and performance. Heat generated in an electronic device needs to be radiated efficiently.

A heat radiating mechanism for radiating heat in an electronic device is used which includes a heat sink and heat radiating fins. The heat sink absorbs heat generated by the electronic components and conducts the heat to an outlet provided in the housing of the electronic device. By feeding air to the outlet, the heat radiating fins make the air absorb heat of the heat sink and the air is exhausted from the outlet. A heat sink may include a heat radiating member and a heat conducting member. The heat radiating member has a plurality of heat radiating fins arrayed at equal intervals. The heat conducting member has a broad surface for conducting heat to the heat radiating member. The arrangement is such that the heat conducting member contacts the electronic components and the heat radiating member faces the outlet. The heat radiating member of the heat sink is interposed between the outlet and a fan which is arranged to feed air to the outlet. Such a heat radiating mechanism being equipped in an electronic device, the heat conducting member of the heat sink efficiently absorbs heat generated by the electronic components and conducts the heat to the heat radiating member, where air from the fan goes through the spaces between each of the plurality of heat radiating fins. As a result, air efficiently absorbs heat and then is exhausted from the outlet, which improves the efficiency of the heat radiation.

2. Description of the Related Art

Conventionally, a heat sink device can have an auxiliary heat radiating member including a plurality of heat radiating fins in the heat sink nearer the fan than the heat radiating member. The plurality of heat radiating fins can be arrayed obliquely with respect to the array of the plurality of heat radiating fins which compose the heat radiating member. Air from the fan may be dispersed by the auxiliary heat radiating member and then enters into the heat radiating member. In this way, this heat sink device can radiate the heat of each of the plurality of heat radiating fins.

A heat radiating member may include a flow path for air formed by the spaces between each of a plurality of heat radiating fins. Air from the fan enters from an air inlet that faces the fan and flows to an air outlet which faces the outlet of the housing to be exhausted out of the housing. If dust or the like caught by the fan clogs the air inlet of the heat radiating member at this time, sufficient air can not be fed into the air flow path between the fins. As a result, the efficiency of the heat radiation may be lowered. An approach to lessen this problem, is to make the interval of the heat radiating fins larger so that dust caught by the fan does not clog the air inlet.

However, if the interval of the heat radiating fins is large, foreign matter entering from the outlet of the housing may pass through the heat radiating member. Thus, the foreign matter may reach the precise electronic components leading to a failure of the electronic device e.g., s a short circuit.

SUMMARY

According to an aspect of an embodiment, an electronic device includes a housing including an air outlet, a heat generating component in the housing and a heat sink in the housing. The heat sink includes a heat radiating member and a heat conducting member. The heat radiating member may includes plurality of heat radiating fins arrayed, the plurality of heat radiating member fins may include a plurality of air flow paths formed between adjacent pairs of the heat radiating fins. An air outlet may face the air outlet of the housing and an air inlet may be located in a side remote from the air outlet of the heat radiating fins. The heat conducting member contacts the heat generating component to absorb heat and conducts the heat to the heat radiating member. A fan may be in the housing feeding air to the air inlet of the heat radiating member to exhaust heat of the heat radiating fins from the air outlet of the housing. The air outlet of the housing may include a plurality of openings arrayed that divide the air flow paths formed between the pairs of heat radiating fins of the heat radiating member, as viewed in the direction looking from outside the housing to the air outlet.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1illustrates an example personal computer that is an example embodiment of an electronic device.

The personal computer10illustrated inFIG. 1may include as an input device an electromagnetic induction type digitizer mounted on the back side of a display screen31, and detect a position on the display screen31indicated by a stylus. By such an example configuration, the personal computer10may input by indication. This input device may be a touch panel mounted on the display screen31, instead of the digitizer and stylus.

The personal computer10may include a main body unit20and a display unit30. The display unit30may be connected to the main body unit20by a biaxial connector unit40so as to be openable and closable in the direction of an arrow A-A and rotatable in the direction of an arrow B-B (about a rotational axis perpendicular to the main body unit20) with respect to the main body unit20.FIG. 1illustrates the personal computer10in a state in which the display unit30is opened with respect to the main body unit20(an open state). This open state may correspond is a first state of use. The main body unit20is an example of a processing unit. The display unit30is an example of a display unit. The connecting portion40is an example of a connector member.

The main body unit20may include a keyboard21, a track pad22, a left click button23and a right click button24. The main body unit20further may include a display unit receiving member34for preventing rattling of the display unit30. The display unit receiving member34is made of rubber, for example. The main body unit20also may include on one side thereof an opening and closing cover26afor an optical disk drive26in which an optical disk such as a CD or DVD is mounted to be driven and accessed. The opening and closing cover26amay include an eject button26bwhich is pressed to open the opening and closing cover26a. The keyboard21is an example of a keyboard.

The display unit30of the personal computer10may include on the front surface thereof a display screen31. The display unit30may include several press buttons32in the right end below the display screen31. The display unit30also may include on the left end thereof a fingerprint sensor33which performs fingerprint authentication by being traced with a fingertip. The display screen31is an example of a display screen. In the open state illustrated inFIG. 1, information is displayed on the display screen31with the direction of the rotational axis B-B of the display unit30as the up-and-down direction.

FIG. 2illustrates a personal computer with the display unit closed over the main body unit. InFIG. 2, the display unit30is in a state of being overlaid on the main body unit20with the display screen31(seeFIG. 1) facing the main body unit20. Hereafter, this state is referred to as a first closed state.

Upon closing the display unit30along the direction of the arrow A from the open state illustrated inFIG. 1, the personal computer10gets in the first closed state, where the display screen31may be hidden inside and the back surface with respect to the display screen31may be exposed outside, as illustrated inFIG. 2. The personal computer10in the first closed state can avoid staining or breakage of the display screen31, providing portability.

As illustrated inFIG. 2, an outlet27is provided in a side of the main body unit20. The outlet27radiates heat generated by various electronic components contained in the main body unit20. The outlet27includes of a plurality of slits27aextending obliquely with respect to the thickness direction of the main body unit20. The outlet27is an example of an air outlet. The slit27ais an example of an opening.

The hot air which has absorbed heat in the main body unit20is exhausted from the outlet27. Since the outlet27is provided in a side of the main body unit20, it will not interfere with operation by a user.

FIG. 3illustrates a personal computer with the display unit rotated substantially 90 degrees with respect to the main body unit.

The display unit30of the personal computer10can be rotated from the state illustrated inFIG. 1via the state illustrated inFIG. 3until the back side of the display screen31faces the front.

FIG. 4illustrates a personal computer, the display unit being overlaid on the main body unit with the display screen facing upward. The personal computer10gets in a second closed state illustrated inFIG. 4upon the display unit30is overlaid on the main body unit with the back surface thereof with respect to the display screen31facing the main body unit20after the display unit30may include been rotated from the state illustrated inFIG. 1via the state illustrated inFIG. 3until the back side of the display screen31faces the front. This second closed state is an example of a second state of use. Hereafter, “tablet mode” refers to an operation mode where the personal computer10is used in the second closed state.

As described above, the display screen31is a display screen with a pen input function, the display screen31having on the back side thereof an electromagnetic induction type digitizer for detecting the indicated position on the display screen. Usually, a user holds the personal computer10which is in the tablet mode with one arm, and operates the display screen with a stylus (not illustrated) in the other hand. In relation to the line of sight upon holding the personal computer10which is in the tablet mode, the displayed image on the display screen31has the orientation thereof rotated 90 degrees from the open state illustrated inFIG. 1. That is, in the tablet mode, information is displayed on the display screen31with a direction perpendicular to the rotational axis of the display unit30as the up-and-down direction.

FIG. 5is illustrates an example internal configuration the personal computer10. As illustrated inFIG. 5, the personal computer10includes a CPU101, a main memory102, a hard disk drive103, a display mechanism104, an input device106, a small recording media drive108, a CD/DVD drive109, an input interface105, an output interface110, a fingerprint sensor33illustrated inFIG. 1and the like. These various elements may be interconnected via bus111. The CPU101executes various programs. In the main memory102are developed programs read from the hard disk drive103for execution by the CPU101. The hard disk drive103stores various programs, data and the like. The display mechanism104conducts processes relating to displaying information. The input device106includes the keyboard21, the track pad22and the like. The small recording media drive108accesses a small recording medium200loaded therein. The CD/DVD drive109accesses a CD-ROM210or DVD loaded therein. The input interface105inputs data from external devices. The output interface110outputs data to external devices. The display mechanism104is comprised of a display controller1041, a display1042and a digitizer1043. The display controller1041controls the direction and the like of information displayed on the display screen31illustrated inFIG. 1. The display1042displays information on the display screen31. The digitizer1043is mounted on the back side of the display screen31and detects the position indicated by a stylus. The CPU101is an example of a processing unit. The display controller1041is an example of a display control unit.

The personal computer10of an example embodiment prevents intrusion of foreign matter from the outlet27illustrated inFIG. 2while at the same time efficiently radiating heat generated by the CPU101and the like.

FIG. 6illustrates the internal configuration of the main body unit20. The main body unit20accommodates various components in a housing20a. The housing20amay include a circuit board on which electronic components500are mounted. The electronic components500include the CPU101illustrated inFIG. 5(not illustrated inFIG. 6since it is under a heat sink300). The heat sink300extends over the plurality of electronic components500to the outlet27. A fan400is arranged nearer the outlet27than the various electronic components500are. The fan400discharges air to the outlet27. The electronic components500is an example of heat generating components.

FIG. 7illustrates the heat sink300.FIG. 7shows the side of the heat sink300opposite the side illustrated inFIG. 6. The heat sink300may include a plurality of fins380in the form of thin plates arrayed in parallel. The heat sink300includes of a heat radiating member320, a heat conducting member310and a heat pipe330. The heat radiating member320is arranged facing the outlet27. The heat conducting member310contacts the electronic components500to absorb heat generated by the electronic components500, and conducts the heat to the heat radiating member320. The heat pipe330extends from the heat radiating member320to the heat conducting member310. The heat radiating member320may include a flow path323for air from the fan400formed by the spaces between each of the plurality of fins380. The heat radiating member320may include an air inlet321facing the fan400and an air flow exit322facing the outlet27respectively formed by the plurality of fins380which are arrayed.

Heat generated by the plurality of electronic components500illustrated inFIG. 6is absorbed by the heat conducting member310and conducted to the heat radiating member320. The heat conducting member310may include a broad surface. The plurality of electronic components500includes electronic components which generate large amounts of heat such as the CPU101, for example. The heat conducting member310is in close contact with the electronic components which generate large amounts of heat. The air inlet321of the heat radiating member320faces the fan400. Air from the fan400flows from the air inlet321of the heat radiating member320into the flow path323and, after absorbing the heat conducted to the plurality of fins320a, flows out from the air flow exit322to be discharged from the outlet27. In an example embodiment, since a heat sink300contacts a plurality of electronic components500, heat generated from the plurality of electronic components500can be efficiently radiated without increasing the size of the device.

FIG. 8illustrates the relationship between the flow path323of the heat radiating member320and the outlet27. As illustrated inFIG. 8, the plurality of fins320ain the heat radiating member320of the heat sink300are provided extending upward in the thickness direction of the main body unit20and arrayed. On the other hand, the slits27aprovided in the outlet27are formed to be oblique with respect to the thickness direction of the main body unit20. Therefore, upon the heat radiating member320of the heat sink300is arranged facing the outlet27, the flow path323of the heat radiating member320is divided by the slit27aof the outlet27.

FIG. 9is an enlarged view around the outlet27of the main body unit20with the heat sink300. As illustrated inFIG. 9, the flow path323formed by the fins320aof the heat sink300is divided by the slit27a. This can prevent a malfunction in which a failure of the personal computer is caused by foreign matter such as trash entering from the outlet27, an accident in which a screwdriver or the like is inserted from the outlet27to short-circuit the electronic component500, and so on. The example embodiment is designed so that the pitch width W1of adjacent fins320ais smaller than the width W2of the slit27a. As a result, the hot air having gone through the flow path323is efficiently discharged from the outlet27. Moreover, an example embodiment prevents intrusion of foreign matter entering from the outlet27. Therefore, the pitch width W1of the fins320aof the heat sink300does not need to be too narrow. In this way, an example embodiment prevents the problem that dust caught by the fan400clogs the air inlet321of the heat radiating member320to lower the efficiency of the heat radiation.

An example embodiment may include a conventional heat sink300. But, the shape of the slit27aof the outlet27provided in the main body unit20may differ from a conventional one. The heat sink300may include a metal of high heat conductivity, which is difficult to work with compared to plastic or the like composing the housing20aof the main body unit20. In an example embodiment, the shape of the slit27aof the outlet27is changed to adjust the relative relationship between the flow path323and the slit27a. As a result, an example embodiment readily achieves both of prevention of foreign matter intrusion and maintenance of heat radiation efficiency without major changes in manufacturing processes.

Although the above example embodiment illustrates an example in which the housing is provided with an outlet in which slits are arrayed, the air outlet may be one in which a plurality of round through-holes are arrayed and divide the air flow path of the heat sink.

Although the above example embodiment illustrates as an electronic device a tablet-type personal computer, the device may be a personal computer not including the tablet function or may be an electronic organizer or the like.

Further, according to an aspect of the embodiments, any combinations of the described features, functions and/or operations can be provided.