TW201144991A - Fanless laptop computer and heat dissipation structure design method - Google Patents

Abstract

The present invention provides a heat dissipation structure design method for a fanless laptop computer. A casing is installed with a motherboard, and is arranged with an I/O interface connector. A heat sink is disposed above the motherboard. The bottom of the motherboard and the top of an aluminum extrusion heat sink are respectively disposed with an aluminum sheet to form a module, which is placed in the rear of a system to be far away from a user, and is used for improving heat conduction, structure strength and anti-electro-magnetic interference efficiency. The system is installed with a keyboard and a front-end battery module to improve the appearance design. Finally, the present invention can achieve the object of providing a fanless laptop computer by means of natural convection. Further, the present invention also discloses a heat dissipation structure design method for a fanless laptop computer.

Description

201144991 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a fanless notebook computer and a method, and more particularly to a type of convection under natural convection. The integrated design method for the configuration of the component system of the cross-checking system m ^ _ the geometry of the plate and the [prior art] Now the axis has the electricity in the market «.«tablet) ^ ^^^,W^(Moblle lnte = Eliminate; choose 1 but generally because of the heat demand, _ will place the tabs, ϋ magnetic Wei flow, to solve the problem of bulk; or _#Structural strength, ΓΪίί disturbance demand, so that the castings. So many products are designed, Low yield and poor product stability, such as common product settings, design considerations, failure to pay attention to heat dissipation, even if the system chip produces very low heat 1 can not be overturned, the secret bottle fan, causing energy waste. Or ignore The protective measures required for electromagnetic interference cause additional cost after the event, delay in development time, or instability in manufacturing. Review of heat dissipation structure design, Xie et al. [Please refer to H. Xie, Μ. Α fine ade, W. lui, K. Haley (1996), “Thermal Solutions to Pentium

Processors in TCP in Notebooks and Sub-notebooks," IEEE Transactions on Components, Packaging and Manufacturing

Technology, part A, Vol 19, No. 1, pp. 54-65] was placed in a notebook computer for the Intel Pentium 75 MHz TCP CPU in 1996. The size is 8. 3n x 12” X 1. r 'not included Display the screen, propose four cooling solutions, including the "heat-dissipation tab and nameplate" solution, using the 0.065" thickness of the L-shaped aluminum plate placed under the board to connect to the TCP CPU, and then 1. 46 Μ X 1. 85 " X 0. 8 Π The heat sink fins are connected to the board, and 30 vents with a diameter of 〇. 32" are opened at the top to handle the TCP CPU 6. 23 W.

Kobayashi et al [please refer to Takashi Kobayashi, TetsuroOgushi, 201144991

Noriaki Sumi, and Masao Fujii (2000), "Thermal Design of an Ultraslim Notebook Computer," IEEE Transactions on Components and Packaging Technologies, Vol. 23, No. 1, pp. 6-13] for Intel MMX Pentium 233 in 2000 The MHz CPU has a thermal design power of 3.9 W. It is placed in a slim notebook (Size: 297 x 218 X 18 mm, Weight: 1.5 kg, Display: 12. Γ) and proposes two new cooling methods. The first way is to use magnesium alloy (Mg die-cast) as the lower cover of the main casing to connect the aluminum heat sink with the CPU 'to transfer heat to the outside of the system by natural convection; the second way is to spray on the magnesium alloy casing New materials allow users to reduce the discomfort caused by temperature. Although the heat dissipation problem has been temporarily solved, the problem of safety regulations such as excessive heat dissipation holes and surface temperature overheating is a matter of concern. Based on the above description, portable electronic products should pay attention to the integrated design method of heat dissipation, structural strength and anti-electromagnetic interference. SUMMARY OF THE INVENTION The main purpose of the present invention is to provide a heat dissipation structure design of a fanless notebook computer, the casing (four) of the wired board, the configuration of the I / Q interface is fresh, the heat sink above the motherboard, in the motherboard Below the heat sink and the top of the heat sink, each piece of aluminum is thin, and the package is cooled into a module - and placed in the rear core of the system to keep away from the user, increasing the '', ', transmission, Μ冓 strength, anti-electromagnetic interference The effect; the system's central keyboard, front bar helps the design. In order to achieve the above-mentioned purpose, in order to achieve natural convection, the fanless notebook computer of the present invention has at least t~a clamshell which has an upper casing and a lower casing, and the upper casing has a -容ϊ:=具!=容室; -The liquid crystal display screen 'located on the first-back end, 1 on the second i-board' is rectangular and placed in the second chamber and a center of τ, /η The processor, a memory rhyme group, and the solid state storage device are respectively, such as a 'recovery body module, a bribe storage device, and a 1/0 connection ° δ " central processor' and the I/O connector is exposed under the Housing; 201144991 = type heat dissipation 'located at the rear end of the second chamber and above the motherboard, the central processing unit contacts 'for heat dissipation; - the upper plate is placed in the name, type, hot film Above and in contact with the brain fins; ― lower Ming thin plate, placed under the δ Xuan, and the enchantment board, and partially overlap with the upper _ plate; - keyboard, system ^ in the middle of the second chamber 'and exposed to the lower casing for input; and - $ battery touch, placed at the front end of the second chamber, and secret to the liquid Display screen, the motherboard and the keyboard, it can supply the direct current power source f. In order to achieve the foregoing objectives, the method for designing a dilute structure of a fanless notebook computer of the present invention includes the following steps: simplifying complex system boundary conditions, and then constructing a three-dimensional heat dissipation simulation of the heat sink model; And temporarily hide the secondary features to simplify the part geometry' and analyze the entire temperature distribution with the GAD/GAE integrated software. In order to provide a further understanding of the structure, features, and objects of the present invention, the detailed description of the drawings and the preferred embodiments are as follows: [Embodiment] Please - and refer to FIG. 1 to FIG. 4b, wherein 1 is a schematic diagram of a fanless notebook computer according to a preferred embodiment of the present invention; FIG. 2 is a schematic diagram of a fanless notebook computer in a cover state according to a preferred embodiment of the present invention; A fanless notebook computer according to a preferred embodiment of the present invention has a transparent view when it is closed; FIG. 4 is a schematic view of the upper side of the heat sink of the preferred embodiment of the present invention; FIG. 4 shows a first embodiment of the present invention. A schematic view of the right side of the aluminum extruded heat sink of the preferred embodiment. As shown in the figure, the fanless notebook computer of the present invention comprises at least: a casing 10; a liquid crystal display screen 20; a motherboard 30; an aluminum extruded heat sink 4; a keyboard 50; The battery module 6 is assembled. Wherein the casing 10 is, for example but not limited to, an injection molded plastic article to reduce its cost, and has an upper casing U and a lower casing 12, the upper casing n and a first chamber 111, the lower The housing 12 has a second chamber 121. /' The liquid crystal display screen 20 is placed in the first chamber U1 for display. Of which, 201144991

The liquid crystal display screen 2G is exemplified by a 12-inch liquid crystal display screen in the present embodiment, but is not limited thereto. - the motherboard 3G has a rectangular design to increase its paste rate, and is placed at the rear end of the second chamber m to have a central processing unit 3 - a memory module - a solid state storage device 33 and a 1 / 〇 connector 34, the memory module 32 state storage device 33 and the 丨 / 〇 connector 34 are respectively coupled to the central processor 31, and the I / O connector 34 is exposed to the lower casing 12 . The central processing unit 31 is, for example but not limited to, a system (System), and the s(6), for example, but not limited to, a solid-state disk module (s) The rear end of the second chamber 121 is located above the motherboard 30 and can be in contact with the central processing unit 31 for heat dissipation. wherein the squeezing type is squeezing, for example, but does not confuse the miscellaneous pressure. The size is 12Q x 32 x 7 (four), and has a plurality of discrete pieces thereon, 'in this embodiment, the H2 h5 p5 domain hot film is taken as an example and is limited thereto, wherein Η is the base height of the heat sink, h The height of the contact piece, p is the rotation=12, is placed at the middle end of the second chamber ,, and the bamboo module 6G exposed to the lower casing is placed at the front end of the second chamber 121, and is lightly connected. To the liquid helium display screen 20, the domain board 30 and the keyboard 50, the required straight, and f-original can be supplied. The Benfa County keyboard 5G towel and the battery module 60 are placed in the lower casing 12 ^ contributes to the design of the housing 10. In the 骽Z, the end portion of the lower housing 12 has a plurality of heat dissipation holes to align the aluminum extruded heat sink 40. And heat dissipation. ",, and - the windless wire type of the present invention has steps - upper plate 14 and lower plate 15 (please refer to Fig. 6), wherein the upper plate is extruded above the heat sink 4 And the heat sink 40 is in contact with the heat sink 4 = ??? The heat sink 40 of the type 201144991 is dissipated. ▲ The lower aluminum sheet 15 is disposed between the lower casing 12 and the motherboard 3 and partially overlaps the upper aluminum sheet 14 The invention is characterized in that the upper aluminum sheet 14 , the main board 3 〇 , the squeeze-type heat sink 40 and the lower sheet g 15 are sandwiched into a module, which can provide heat dissipation and electromagnetic wave interference prevention functions, and can be enhanced. The structural strength of the fanless notebook computer of the present invention designs the motherboard 3〇 as a rectangle to improve the utilization ratio, and places the motherboard 30 and the 1/0 interface connector 34 behind the system to remove the user. The central keyboard 5 〇 and the front battery module contribute to the design and heat conduction; in addition, the present invention utilizes the upper aluminum sheet, the motherboard, the I squeezing heat sink 40 and the lower Ming board The 15 packs are clipped into a module, which can provide heat dissipation and anti-electromagnetic interference, and can enhance its structural strength. The fanless notebook computer in this case does not need a fan to achieve the required heat dissipation effect. It is indeed more advanced than the conventional pen S-type computer. In addition, the present disclosure also discloses a fanless notebook computer thermal module design. The method comprises the steps of: simplifying complex system boundary conditions (step υ; performing a three-dimensional heat dissipation simulation of the constructed heat sink model 40 (step 2); and temporarily hiding secondary features to simplify part geometry and utilizing CAD /CAE integrated software to analyze the entire temperature distribution (step 3). The CAD/CAE integrated software is pro/E. The heat sink model 4 is aluminum extruded heat dissipation made by aluminum extrusion technology. The chip has a maximum outer dimension of 12〇X 32 X 7 〇nm) and has a plurality of heat sink fins thereon. The design principle of the heat dissipation module design method of the present invention is as follows: for the design of a low-cost notebook computer mechanism, heat dissipation is still the most important subject, and it is desirable to utilize metal geometry and good heat conduction without a fan and a heat pipe. Features, using natural convection (Natural Convection) to reduce heat and reduce costs. Newton s Law of Cooling [Please refer to 丫 (10) This A. Gengel (2004), Heat Transfer: A Practical Approach 2nd

Edition in SI Units, Singapore: McGraw-Hill, pp. 812-816 ] 201144991 The relationship is Q - tic A (Theat sink — Tair ) (Formula 1) It is known that the present invention reduces the temperature of the wafer in two directions (1) Increase the surface area of the heat sink (A) '(2) Lift the surface temperature of the heat sink (Theatsink), in other words, let the heat transfer rate (Q) of the wafer be quickly transferred to the surface of the heat sink. Since the air is a natural convection condition, its convective heat transfer coefficient (h<〇 is about 5-25 (W/m2.°C), ambient air temperature (Tair) is relatively difficult = text change. In engineering, although copper metal The heat transfer coefficient is greater than that of aluminum metal, but it is limited by the size, weight and price of the heat sink. Aluminum extruded metal (1〇5〇) is still selected as the heat sink.

The heat transfer design of the heat dissipation system is often evaluated by "The Service Resistance (R)". The thermal resistance relationship between the wafer surface and the ambient temperature is (Equation 2).

Rc-a - (Tease - Tair)/Qd where

Rc-a is the thermal resistance of the wafer surface to ambient temperature (.c/w)

Tease is the surface temperature of the chip package (.〇Tair is the ambient temperature (°〇Qd is the power consumption of the chip (w). The thermal resistance==the heat dissipation capacity is poor; on the contrary, the small size indicates that the heat dissipation capacity is good. The temperature rises with time after startup. , knife cloth. Because the general electronic H2 h5 is the largest 2 = inch is 120 X 32 x 7 (mm) 'The heat sink is shown in Figures 4a and 4b., p = 5) thermal load position and detail size, The full t degree (6) and the paste distance (five) are used as variables. The basic conditions of the simulation software are set: 201144991 (1) Model Setting:

Material Assignment: The ugly 1 c〇nductiv guide), k = 209 (W/m.°C) heat

Heat Load: 6 w

Constraint (restriction): he= 5, 1(), 15, 2〇, 25(w/m2. °C ' db (2) Analysis: Steady_state (Stable) Use CAD/CAE integrated software to quickly simulate each ^ The surface temperature of the wafer body (τ(10)), and observe the relationship between them, find the lower τ_, which means that the heat sink has more heat-dissipating pants. _ It is known that the spacing (ρ) is higher, and the lower the τ(10) 22:00 is the lowest; in each ratio, the heat sink H1 h6, H2 h5 Tcase value is lower than HO. 5 h5. 5, H3 h4. 竿乂师Γ】This 'a stage of the experiment will be the heat sink H1 H6 P3, H2 h5 P3 is made into real M in 'another heat sink H2 h5 P5 as the experimental control group, for the above three groups of scattered ===6 W, he = 10 W/m2, C simulation values, as shown in the table} Shown in Figure 1. The distribution in 1 is shown in Figure 4. These simulation results will help to reduce the production of the body and help to reduce the cost of product development. Table 1 When the Qd = 6, hc = 10 heat sink simulation values Heat sink_Type H Ui6 p3 H2 Ιι5 H2 h4 Temperature difference ΔΓ(°〇6.0 4.2 4,6 Maximum temperature and lowest temperature^case (°C) 7~— (.〇68.5 62.5 70.9 66.7 78.8 74.2 Fig. 3ϊ15Η The heat-dissipating module of the heat-dissipating module of the present invention is connected to the heat-dissipating module, and the verification galvanic green n 糸, the advanced test 5 and the steps are as follows: (1) placing the T-tyPe heat and the end point - Between the gap 40 and the heating simulator (HS1) llG

S 9 201144991 Heart point 'combined lion touch; (2) will heat the simulation ^ η sequentially connect the positive and negative poles of the thermocouple wire (10) to the positive and negative poles, and the piece 40; (3) the power supply of the analog device m is just turned and turned on) The heating piece and the heating power = finely taken soft body 161 'sequentially record different heat dissipation, and the constant temperature control box 13 〇 sets L = 35 τ. Table Temperature test on the surface of different heat-sensitive analog chip package ^ (^ hot film t low temperature test value (Τ _, coffee)., (Cai e. Coffee) and most

Table 2 each group of heat sinks at different heating powers (.〇

Ic^se,test : Simulated chip package surface temperature test value TV top : Top cover bracket maximum temperature test value Tal btm : lower cover bracket maximum temperature test value TP1, top ·· host cover maximum temperature test value Tpl, btm: under the host Cover maximum temperature test value 3.20 (Review / melon...) r 3. 20 (W / m.0 〇 TP1: heat transfer sheet 120 X 7 X 0. 5 〇 M 〇, k = TP2 · Thermal conduction shi film 120 x 23 χ 2. 0 (mm),k 201144991 This section is located on the center line of HS1. The test results of each point are made by three sets of heat sinks, TP1 and TP2, as shown in Table 3. Table 3 System temperature value (X)

Kt HS1. No. · QdW) I^Al, lop TaI. btm T^btm ^ca Hl/i6p3 + TPl 1 7.03 75.0 HI Λ6ρ3 + ΤΡ1 +TP2 60.8 64.8 49.4 53.2 5.69 2 7.58 75.0 65.7 67.0 53.9 54.8 5.28 H2/ !5p3 + TPl 3 7.66 75.0 Η2; ι5ρ3 + ΤΡ1 + TP2 62.1 59.5 50.0 55.5 5.22 4 8.25 75.0 65.7 64.5 52.5 55.9 4.85 H2h5p5 + TPl 5 7.31 75.0 //2Λ5/75+ΤΡΙ +TP2 61.0 65.1 50.1 54.9 5.47 6 7.86 75.0 63.6 64.5 51.2 54.9 5.09

The following description shows that the present invention designs the heat sink 40 by CAD/CAE integrated software simulation and then compares it with the experimental results. The relationship between the heat sink and the system experiment is found, and the thermal resistance is used to evaluate the performance and verify the design result. Please refer to FIG. 7 , which shows the relationship between the ratio of each heat sink and the relationship between the ships when Qd = 6 w. Among them, the relationship between the hc of the simulated heat sinks H1 h6 P3, H2 h5 p3, H2 h5 p5 and Tease is as follows: (1) The larger the s he value, the closer the Tcase values of the three heat sinks represent the heat sink geometry. Does not affect the heat dissipation efficiency, but he = 5_1 〇 (W / m2.. ^ ^, larger. (2) When the heat sink is Qd = 6 w, the highest surface temperature test value d is substituted into the simulation curve of Figure 7, by interpolation The heat sink m诎p3, H2 201144991 H2 h5 P5 hc value is 7. 5, 8.7, 9.4, as shown in Figure 7. This shows that the constant 3 box is not only from the air, but also Measure the heat dissipation (4) What shape of the heat dissipation effect. In the solid model system experiment, when Tease, test = 75, the conduction Qd of the three sets of heat sinks is greater than 7 W, which is to paste two thermal film (τρι + The condition of τρ2) is better than that of the paste-block heat-conductive chip (ΤΡ1), as shown in Table 3. In the experiment, the film Η 2 h5 Ρ 3 + ΤΡ 1 + ΤΡ 2 can conduct Qd = 8. 25 w.

Using the formula (Equation 2), the heat dissipation simulation and experimental results are evaluated by thermal resistance to evaluate the dispersion contribution = performance 'thermal resistance is large, indicating that the heat dissipation capability is poor; otherwise, the small touch indicates the divergence capacity = ^ Table 4 knows that In the heat sink simulation or experiment, the heat resistance of the heat sink hi(10) and H2 h5 P3 is less than that of the experimental control heat sink H2. 1 m

H2 h5 HI h5 p5 8.74 10.7 7.47 8.08 5.22 5.47 4.85 5.09 In the test, 'heat sink H2 h5 p3 by heat conduction stone film (1?1) more cover bracket to increase heat dissipation, heat _ 7. 47 drop. j; Let the thermal conductive film (TP1 + TP2) then β "second, the use of two brackets in addition to (four) Du Bing two for 4. 5 ((10)). This shows a part of the upper cover. ° ° also helps the heat dissipation effect, It can be regarded as a heat-dissipating module, which is designed to be rectangular, that is, away from the makers, and tender, with the financial heat conduction of 201144991, and the 'this (four) II by the upper heat sink and the next _ The board is sandwiched into a surface, except for the machine board and the cymbal type, "the field is sturdy and the strength is strong, so that the fan can be used to achieve the snow simmering effect" can reduce the manufacturing cost. Therefore, the present invention is indeed more conventional. The notebook is progressive. The disclosure of the & & 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 category. About 'inferred person'

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a schematic view of a preferred computer of the present invention. Fanless Description of Bell' Figure 2 is a schematic view showing a schematic view of a comparative computer of the present invention when it is closed. Fig. 3 is a schematic view showing the intent of a computer of a preferred embodiment of the present invention when it is closed. ..., fan pen Fig. 4a is a schematic view showing the upper side reading and the drawing of one piece of the present invention. The secret - the intent of the heat sink type, riding the show (four) - difficult to implement the example of the bribery heat = = shift map, turn the forest to send the batch of the Chi Chi to connect the physical model system Figure 6 is - schematic ' It shows a schematic cross-sectional view of the heat-dissipation temperature test point of the present invention. , W ′ each of the fins and Tcase Figure 7 is a schematic diagram, the green shows a schematic diagram of the Qd relationship. [Main component symbol description] Upper casing 11 Lower casing 12 Chassis 10 First chamber 1Π 13 201144991 Second chamber 121 Upper aluminum sheet 14 Liquid crystal display 20 Central processing unit 31 Solid-state storage device 33 Ming-extrusion type Heat sink 40 Battery module 60 Heating simulator 110 Thermostatic control box 130 Computer 160 Cooling hole 13 Lower aluminum sheet 15 Mother board 30 Memory module 32 I/O connector 34 Keyboard 50 T-type thermocouple wire 10 0 Temperature撷Take system 120 power supply 140 data capture software 161 reference 14

Claims (1)

201144991 VII. Patent application scope: 1. A fanless notebook computer, which comprises at least: - a casing having an upper casing and a plenum, the lower casing having a second chamber; a mountain having - The first liquid crystal display screen is placed in the first chamber. The second middle portion is rectangular and placed at the rear end of the second chamber, and has a central processing unit, a memory module, and a solid state. a storage device and a Γ;; ; / 〇 ® I / O central processing unit and the 1 / 0 connector is exposed to the lower casing; square; = ΐ heat sink 'located at the rear of the second chamber and located Above the motherboard, it can be turned over with the towel, and the film is contacted with the film. The film is placed on top of the transition heat sink and is placed in the lower casing with the transformation heat sink. The domain system, the portion and the upper input button 5 and the middle of the second chamber are exposed, and exposed to the lower casing, which can indicate that the tether is placed at the front end of the second chamber, and is reduced to The liquid crystal display screen, the motherboard and the keyboard can supply the required DC power supply. Among them, the one of the t t 如 申 申 5 The fanless notebook computer described in Item 1 of the monthly patent is an injection molded product, and the size of the liquid crystal display is a system on chip (SoC). The fanless notebook computer described in the first paragraph of the patent range can be sandwiched into a module eight heat release and anti-electromagnetic interference function, and the structural strength can be enhanced by the reverse, the motherboard, the indented heat sink and the lower plate. A fanless notebook computer as described in claim 1 of the claim 5, wherein the storage device is a solid state disk module (SSD). 5. As claimed in claim 1, A fanless notebook computer, in which the 15 201144991 embossed embossed embossed embossed into a hybrid, with a maximum dimension of (10) X 32 X 7 (mra) and a plurality of fins thereon. · If you want to apply for the special _ 5 items, the shape of the windless silk is one (4), where Η is the base of the heat sink, th is the fin orientation, and p is the fin spacing. The fanless notebook described in the first item Computer, where the L '卩 has Wei's voyage 'Jianchi squeezed Wei system convection and dispersion<»> The step-by-step fan of the fan-type electric fan is designed to be green, which includes simplifying the complicated system boundary conditions; ϊίίίΞϊ heatsink model to perform three-dimensional heat dissipation simulation; and the symmetry software to divide the part geometry (10) Thinning the design method of the axis only, wherein the heat dissipation is one piece (four) _ design record, and a squeeze type heat sink made of a size of 12 〇 x ?, the maximum -1 κ υ XX 7 ( Mm), and 1 LQ has a plurality of heat sink fins. 16