TW200930899A - Cooling apparatus - Google Patents

Abstract

A piezoelectric fan (31) is configured by bonding a blade (21) to a piezoelectric vibrator (20) which bends corresponding to voltage application, and the blade (21) of the piezoelectric fan (31) is made to swing within a space between heat dissipating fins (30, 30) to which a heat sink adjoins. Amplitude of the blade (21) is increased by forming an opening section (22) on the blade (21), and cooling performance is improved by increasing discharging effects of high temperature air close to the wall surface of the heat dissipating fin (30).

Description

200930899 IX. Description of the Invention: [Technical Field] The present invention relates to a cooling device using a piezoelectric fan for discharging heat inside an electronic device to the outside of the electronic device. [Prior Art] In recent years, in particular, portable electronic devices have become a subject of thermal countermeasures within electronic devices as miniaturization and high-profile installation of components have progressed. An example of a portable electronic device that is particularly important as the above-mentioned problem is a portable personal computer. In the portable personal computer, the development of technology for miniaturization is progressing, and the speed of cpu for improving information processing is progressing. Therefore, the high-density mounting of the member causes the ventilating property inside the electronic device to drop linearly, and the heat generated by the CPU is increased, and the heat is discharged to the outside of the electronic device to suppress the temperature rise inside the electronic device. First, if the heat sink connected to the heat generating portion of the heating element is vacated, and a plurality of heat sinks are provided with a movable piece containing air, the rotating piece Q or the movable piece is sent to send cold air between the heat sinks. A radiator-like radiator that discharges between the fins is as shown in Patent Document 1. On the other hand, a piezoelectric fan having an outlet vibrator including a piezoelectric vibrator and an exhaust port and an intake port provided on the same surface is disclosed in Patent Document 2. The piezoelectric fan is provided with a pair of partitions extending inward from the opening of the box body, such as sandwiching the two sides of the wind vibrator, and the openings between the partitions and the two sides of the box body are formed. For the suction port, the opening formed by sandwiching the two partitions is formed as an exhaust port. Here, the composition of the electric fan of Patent Document 2 is based on the figure! Said 134432.doc 200930899 Ming. In Fig. 1, a fan fan i houses a fan body 5 composed of a piezoelectric vibrator 3 and an outlet vibrator 4 in a fan case 2 formed in a flat box shape, and forms an air suction on the same side of the fan case 2. Port 6 (6A, 6B) and exhaust port 7. The fan case 2 is made of a case body 8 having a bottom surface portion 8a, left and right side surface portions 8b and 8c, and a back surface portion 8d, and is opened at the front surface portion, and is airtight on the upper surface of the box body 8. The flat cover 9 is formed. [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. If the radiator of Patent Document i is used as it is, it is not suitable from the viewpoint of miniaturization. In view of &, it is considered to replace the movable piece of Patent Document 1, and an electric fan as shown in Patent Document 2 is used. When a dust electric fan is used, the air blowing capacity depends on the displacement amount of the ® 振动 electric vibrator in the wind vibrator, but the displacement amount of the piezoelectric vibrator and the movable piece of the document 1 are large. Therefore, it is necessary to consider the cooling of the inside of the electronic machine as efficiently as possible. Patent Document 2 describes that the interval between the two separators is basically as close as possible to the width of the air outlet plate, that is, to minimize the two partition plates and the air outlet plate: the gap. 'The heat is used to discharge the heat between the heat sinks of the radiator of the patent, even if there is (4) the air moving in the movable piece ", such as the strong driving source of the motor rotates or oscillates", the action of the movable piece is not 134432 .doc 200930899 will be hindered by the influence of air resistance, and the wind vibrator of the piezoelectric fan of Patent Document 2 will be 'if the interval between the fins of the two partitions is close to the width of the air outlet plate' The displacement is hindered by the air resistance generated by the action of the wind vibrator.

Here, the relationship between the amplitude of the front end of the air outlet plate (hereinafter referred to as "blade") obtained by the inventor of the present invention and the air resistance is as shown in Fig. 2. The resulting piezoelectric vibrator has a size of 6 mm x 12 mm and a blade size of 6 mm x 18 mm x 40 μη, which are joined to each other by short sides. Since the air resistance is substantially proportional to the air density and the air density is proportional to the air pressure, the experiment was carried out by investigating the air pressure when the blade is driven by the piezoelectric vibrator in a specific decompression environment and the amplitude of the tip of the blade. As shown in Fig. 2, the amplitude of the cymbal is affected by the air pressure, that is, the air resistance. The larger the air resistance, the smaller the amplitude. In this way, even if the interval between the fins corresponding to the two spacers is as close as possible to the width of the blade, the displacement will be hindered by the air resistance generated by the action of the blade, and there is a problem that it is difficult to increase the amplitude of the blade. . Therefore, the object of the present invention is to provide a large blade amplitude to improve the air blowing capability, and a thermal effect to improve the cooling capacity [technical means for solving the problem] a cooling device which can increase the dissipation factor from the heat sink. The heat to be discharged is heated by the heat sink for a long time / 71 stops 13⁄4 temperature part, so the temperature distribution of the space between the heat sinks is not even near the wall surface of the heat sink. Also consider the flow velocity distribution when the air flows between the fins, although the center of the heat sink is 134432.doc 200930899. The flow rate of P air is fast, but since there is viscous resistance of air relative to the wall surface of the heat sink, the flow velocity toward the wall surface of the heat sink is slower. That is, only the air flowing between the fins is simply discharged, and the air having a relatively low temperature in the central portion between the fins is discharged, but the high-temperature heater existing near the wall surface of the fins is not sufficiently discharged. . The inventors of the present invention have found from various experiments and simulations that regardless of whether or not the air between the fins is completely discharged by the vanes, if the heat is applied to the vicinity of the wall surface of the heat sink 4, the heating is performed. By moving to the center portion between the fins so that the heater is easily discharged, the heat inside the electronic device can be efficiently and efficiently discharged to the outside of the electronic device. Therefore, the present invention is constructed as follows. (1) A piezoelectric fan having a piezoelectric vibrator that is bent according to a voltage application and a blade that is or is oscillated by the piezoelectric vibrator to be oscillated by the piezoelectric vibrator, and having at least two heat sinks In the heat sink of the sheet, the blade is formed in a strip shape extending from the piezoelectric vibrator, and the piezoelectric vibrator is disposed so as not to abut against the fin and oscillate in a space between adjacent fins. And the blade, wherein the blade is provided with an opening or a notch. With this configuration, the air resistance is reduced by the opening or the notch, and the amplitude of 'U is increased. Even if the overall air volume caused by the opening or the notch is lowered, the effect of cleaning the heater near the wall surface of the heat sink is not lowered, and the overall cooling capacity is improved with the increase of the vibration field. In addition, since the heating flow near the wall surface of the loose rail piece is peeled off and flows toward the center portion, the heat in the vicinity of the heat sink is preferentially removed, so that the heat dissipation effect is improved, and the cooling energy is increased by 134432.doc 200930899. (2) A weight may be provided in the vicinity of the front end or the front end of the blade away from the piezoelectric vibrator side. With this configuration, the moment of inertia is increased by the weight, and is driven by the resonance frequency of the blade including the weight, whereby the amplitude of the blade is increased. Therefore, the cooling capacity will increase. (3) The blade may have a zigzag shape in which the longitudinal direction of the long strip is shortened. With this configuration, the full length of the blade will increase and the amplitude will increase. Therefore, the cooling capacity will increase. (4) The piezoelectric vibrator is disposed such that the end portions of the vanes are sandwiched from both sides. The piezoelectric vibrator and the vane may be formed as a bimorph type vibrator. With this configuration, the amount of bending displacement with respect to the applied voltage will increase, and the amplitude of the blade will increase. Therefore, the cooling capacity will be further improved. (5) For the heat sink, a fan that generates an air flow may be disposed between the sidewalls of the heat sink in the air flow direction. According to this configuration, the heating flow in the vicinity of the wall surface of the fin is separated by the presence of the opening or the notch, and the heater that flows in a wave direction toward the center portion flows out efficiently by the additional fan, and the overall cooling capacity is improved. (6) The opening portion has a long shape along the longitudinal direction of the blade, and a dimension from a side in a longitudinal direction of the blade to a side of the opening parallel to the side is larger than a gap between the fin and the blade Big. Thereby, a higher cooling capacity can be obtained. 134432.doc 200930899 [Effect of the Invention] According to the present invention, the amplitude of the blade will increase and the cooling ability will be improved. In addition, at the same time, the heat dissipation results from the heat sink will increase and the cooling capacity will increase. [Embodiment] «First Embodiment" Fig. 3 is a diagram of a piezoelectric fan used in a cooling device according to the first embodiment. The piezoelectric fan 图 in Fig. 3 is composed of a blade 21 having an opening 22 and a piezoelectric vibrator 2G. The piezoelectric vibrator 2() is a bimorph type piezoelectric vibrator in which piezoelectric elements are arranged on both surfaces of a metal plate as an intermediate electrode. That is, the piezoelectric element 'on both sides of the metal plate as the intermediate electrode of the piezoelectric vibrator 2' forms an electrode film on each surface, and the electrode is applied to the metal plate as the intermediate electrode by applying a corresponding The driving voltage in the polarization direction of the piezoelectric element is subjected to polarization processing (10) bending in the longitudinal direction (L1 dimensional direction) to perform bending vibration. The cymbal sheet 21 is formed so as to penetrate the rectangular opening portion 22 with respect to the non-recorded steel sheet, and the end portion thereof is followed by the end portion of the piezoelectric vibrator 2 . The dimensions of the respective portions of the piezoelectric fan shown in Fig. 3 are as follows. L1 : 12 mm * L2 : 18 mm W : 6 mm t : 50 μιη Another 'opening 22's 卄 soap μ ^ 2 12 mmx2 mm 'The end near the root coincides with the end of the piezoelectric vibrator 2〇 . 134432.doc -11 - 200930899 Fig. 4(A) is a perspective view showing the main part of the cooling device in which the piezoelectric fan 31 shown in Fig. 3 is disposed at a specific position of the heat sink. In the heat sink, a plurality of fins 30 as shown in Fig. 4 are protruded in parallel with each other, and the adjacent fins 3 are arranged such that the blades 21 of the piezoelectric fan 31 do not abut against the fins 30, and the electric fan 31 is arranged in a swinging manner. Fig. 4 (B) is a front view of the entire cooling device as seen from the direction in which the fins extend (the direction opposite to the blowing direction). The heat sink 40 is provided with a plurality of fins 3 延伸 extending in parallel with each other. In this example, a heat generating body (heat generating member) 110 such as a CPU is mounted on the upper portion of the circuit board 120, and the bottom surface of the heat sink is disposed on the upper surface of the 11 〇. Thus, the heat sink 40 and the plurality of piezoelectric fans 31 constitute a cooling device 100°. FIG. 5 is the presence or absence of the opening 22 provided in the blade 21 of the piezoelectric fan 31 shown in FIGS. 3 and 4, and the heat sink 3〇. The presence or absence of an indication of the amplitude variation of the leading end of the blade. Thus, if there are fins on both sides of the blade, the amplitude of the tip of the blade will be reduced as compared with the case of an open space. For example, when the input voltage is 3 〇 V and there is no opening, the amplitude of the tip of the blade is 9.2 mm with respect to the case without the fin, and the amplitude of the tip of the blade is reduced to 5.5 mm when the fin is present. However, by providing the opening portion 22, the amplitude of the leading end of the blade can be increased to 7.5 mm. This is because the substantial area of the oscillating vane 21 is reduced by the presence of the opening portion 22, and the extraction air is improved by the opening portion 22 as will be described later, and the air resistance is correspondingly reduced. By providing the opening portion 22 in the blade as described above, it is understood that the amplitude swinging blade can be relatively large even in the space between the fins. Fig. 6 is a schematic view showing the effect of the opening portion 22 provided on the blade 21; the electric fan 3! The support portion (the left end in the figure) of the piezoelectric vibrator 2 is the middle blade 2; The arrows u and d oscillate. Thereby, the air in the space sandwiched by the fins 30 flows as the air flow indicated by the arrow A f. At this time, the airflow passing through the opening 22 from the upper side to the lower side and from the lower side is also turbulently mixed with the upper side and the lower side of the blade 21. In addition, (4), the heating flow near the wall surface of the heat sink 30 is separated from the side edge of the blade, and the heating is directed toward the opening portion 22, that is, the two adjacent heat sinks 3 are sandwiched between the two kings. The direction of the central part flows. The portion 22 is not only reduced in the air resistance to increase the amplitude of the blade η, but also in the vicinity of the wall surface of the heat sink 30, and is removed together with the overall airflow in the space sandwiched by the heat sink 3〇. The external mouth is like a role. (Here, the current work of the field from the field ‘, .^ ” is called “sweeping effect”

This can improve the heat dissipation effect. Fig. 7 is a diagram showing the presence of an opening. In Fig. 7, the low-intensity #片丽丽电风扇 has a high effect, and the low part is divided into a low temperature region, and the high-brightness portion is meat, and the so-called (he field 〇v is the airflow of the cold space constructed as shown in Fig. 4). Although the temperature distribution is (4), the space between the S-hot sheets is large, and the 3D simulation is required. However, due to the large amount of calculation, the two-dimensional simulation is replaced here. 134432.doc 200930899 Figure =) Two fins 3 adjacent to each other. The sound distribution of the temperature distribution in the case where the heat sink 3G is in the space sandwiched by the heat sink 3G and the cold air flowing at a specific temperature from the right direction is thus sandwiched between the heat sinks 30. The flow in the space; the flow is closer to the central part of the space. This is the case. For the layer T, the wall surface of the heat sink 30 is theoretically flowable due to the dry resistance of the air. Therefore, the flow from the left end... The central portion of the space in which the wind passes through the heat sink 30 is still two

The amount of wind flow to the right end is large, and the heat sink 30 has a low heat dissipation effect. 7 Fig. 7(8)' is a schematic representation of the temperature distribution of the case where the wall of the heat sink 3 is vibrated in the left and right directions in the figure. Other conditions are the same as in (8). This is equivalent to the portion on both sides of the opening portion ^ in the blade 21 shown in Fig. 4 . The heat (high-temperature air layer) thus distributed on the wall surface of the heat sink 30 flows toward the center of the space to be swept away as it flows through the air flow in the entire space. Therefore, the overall heat dissipation effect can be improved. «Second Embodiment" In the first embodiment, the single opening 22 extending in the longitudinal direction of the blade is formed with respect to the blade 21. However, Fig. 8 is a schematic view of a piezoelectric fan having two different configurations. In the example of Fig. 8(A), the piezoelectric fan 32 having the notch portion 23 extending in the longitudinal direction of the blade 21 is formed at the front end portion of the blade 21 (away from the side of the piezoelectric vibrator 2). In the structure shown in Fig. 8 (Α), the position of the opening may be arranged at the front end of the blade 21. Thus, even if the notch portion 23 is formed at the end portion of the blade 21, the effect of increasing the amplitude of the blade 2 and the effect of sweeping the high temperature air of the wall surface of the fin can be obtained by the reduction of the air resistance. In the example of Fig. 8(B), the blade 21 in which the plurality of openings 22a to 22d are formed is joined to the piezoelectric vibrator 20 to constitute the piezoelectric fan 33. The difference in the effect of the position and number of the openings facing the blades 21 is as follows. First, as shown in FIG. 3, the opening portion 22 is formed near the root portion of the blade (the side of the piezoelectric vibrator 20), and since the opening portion 22 is present at a small oscillating position of the blade 21, the air resistance is small. The effect of the reduction is small, and the effect of increasing the amplitude of the blade 21 is small, but the effect of the air being pushed out at the tip end portion of the blade 21 is not lost by the opening portion, so that the air blowing property is high. On the other hand, when the notch portion 23 is formed in the vicinity of the end portion of the blade 21 (or the opening portion is formed in the vicinity of the tip end portion) as shown in Fig. 8(A), the effect of reducing the air resistance is high and the amplitude of the blade 21 is increased. Therefore, the sweeping effect of the high temperature air on the wall surface of the fin is increased. However, since the effect of the air flow from the tip end portion of the blade is lowered, the air blowing property is lowered. 〇 Because the airflow and sweeping effects are somewhat compromised, the shape, position, and size of the opening can be determined in such a way as to obtain the highest cooling capacity. Further, even if a plurality of openings are provided as shown in Fig. 8(B), the size, formation position, number, and the like of the openings are determined in consideration of the air blowing property and the sweeping effect. In the case where the opening portion is formed in the vicinity of the root portion of the blade (the side of the piezoelectric vibrator 2〇), the bending stress of the blade 21 makes the substantial width of the relatively large position small, but the opening portion 22 is not The shape extending in the longitudinal direction of the blade 21 in the width direction 134432.doc -15-200930899 can alleviate the concentration of bending stress and ensure the reliability in long-term driving. «Third Embodiment> Fig. 9 is a perspective view showing a piezoelectric fan used in a cooling device according to a third embodiment. In this example, the piezoelectric fan 34 is constituted by the blade 21 having the opening 22, the tip end portion having the weights 24a and 24b, and the piezoelectric vibrator 20.

❹ The weights 24a and 24b are made of stainless steel in the same manner as the blades 21, and are joined by an adhesive. The figure of the weights 24a, 24b has a dimension L3 of 2 mm and a d of 0.5 mm. The other blade 21 has a thickness of 100 μm. The other dimensions u, L2, and W are the same as in the first embodiment shown in Fig. 3 as [1 = 12 mm, L = 18 mm, and W = 6 mm. The position and size of the opening 22 are the same as those shown in Fig. 3. Park υ is equipped with -Vt five. A schematic diagram of the effect of Lihan's opening. It can be seen that a larger amplitude can be obtained by the fact that the counterweights 24a, 24b and the opening 22' are vibrated in the open space compared to the piezoelectric fan which is not provided with the counterweight and the opening. For example, when the input voltage is 3GV, the amplitude of the tip of the blade is about 5.5_ in the case where the counterweight and the piezoelectric fan are not provided in the opening, but the counterweight and the opening are not shown in Fig. 1 . In the case of an electric fan, the amplitude of the front end of the blade is increased to 9.5 mm. Because of the weighting of the moments 24a, 24b at the front end of the blade 21, the moment of inertia is increased by the weight, and by the inclusion of the matching, even at the resonant frequency as shown in FIG. In the case of the fan 34, the amplitude of the pressure vanes 21 can be increased in the space in which it is accommodated. Therefore, it can improve the cooling capacity of 134432.doc 200930899. In addition, the addition of the weight has a multiplication effect with the formation of the opening. This is because the addition of the counterweight and the formation of the 'part makes the center of gravity of the blade move toward the front end portion'. The inertia moment per mass of the blade is large. Therefore, since the weights of the blades are also increased by the weights 24a, 24b, the sweeping effect produced by the opening portion 22 can be further improved. «Fourth embodiment" Fig. 11 is a perspective view of a waste electric fan according to a fourth embodiment. In this example, the openings 22b and 22c are provided, and the entire blade is elongated, and the blade 21 that is bent so as to be shortened in the longitudinal direction and the piezoelectric vibrator 20 that is joined thereto constitute the piezoelectric fan 35. With such a configuration, the full length growth II of the blade 21 is driven by the resonance of the diaphragm 21 at the fundamental frequency to increase the amplitude and the cooling force. Further, although the blade 21 has a long overall length, the length dimension can be shortened as a whole, so that the overall size of the cooling device can be suppressed and the cooling capacity can be improved. Further, in this example, the blade 21 is divided into three portions as shown by 21a, 21b, and 21C, and an opening portion is not formed in the portion 21a near the piezoelectric vibrator 20, and openings 22b and 22c are formed in the portions 21b and 21c. . Further, the openings 22b and 22c are formed avoiding the meandering portions. With such a configuration, the elasticity of the root portion of the piezoelectric vibrator is enhanced, the elasticity of the tip end portion is weakened, and the amplitudes of the portions 21b and 21c (especially the amplitude of 21c) are increased. Therefore, it is possible to obtain a high air blowing capability by swinging in a fan motion. In addition, since the stress is not concentrated in the opening portion, reliability in long-term driving can be ensured. ^ 134432.doc 200930899 In addition, the front end of the blade of the meandering structure or the specific space may be fitted with a counterweight as shown in FIG. «Fifth Embodiment> Fig. 12 is a side view showing a piezoelectric fan according to a fifth embodiment. Each of the embodiments shown so far is based on the type in which the piezoelectric vibrator 2' is joined to one surface of the blade 21. However, the piezoelectric fan 36 shown in Fig. 12 is configured such that the end portions of the vane 21 are sandwiched from both sides. The electric elements 20a and 20b constitute a bimorph type vibrator by the piezoelectric elements 2a and 20b and the vane 21. An electrode film is formed on each surface of the piezoelectric elements 20a and 20b, and the piezoelectric element 20a is formed between the electrodes and the blade 21 by applying a driving voltage corresponding to the polarization directions of the piezoelectric elements 2a and 2b. 20b is stretched in the opposite direction to drive as a bimorph type piezoelectric vibrator. With such a bimorph type, the piezoelectric elements 2a, 2b can increase the amount of bending displacement of the blade 21 with respect to the applied voltage, and the amplitude of the blade 21 can be further efficiently increased. ❹ In FIG. 12, the example in which the opening 22 is formed in the piezoelectric fan of the blade 21 is shown, but the configuration in which the weight is attached to the front end of the blade 21 as shown in FIG. 9, or the pressure of the curved structure of the blade 21 as shown in FIG. Electric fans are also suitable. 'The sixth embodiment>> Fig. 13 is a perspective view of a piezoelectric fan used in the cooling device of the sixth embodiment. The respective ends of the two piezoelectric vibrators 26a and 26b as shown in the figure are joined to each other via the spacer 28 to form a U-shaped piezoelectric vibrating subunit, and the end of one of the piezoelectric vibrators 26a is connected to the blade via the spacer 29. The 21 joint constitutes the piezoelectric fan 37. In this example, the opening portion 22 is formed in the blade 21. 134432.doc 18 200930899 The other aforementioned cymbals 28, 29 are not required. Fig. 14 is a view showing a bending mode at the time of voltage application of the U-shaped piezoelectric vibrating subunit. Fig. 14(A) shows a state in which the applied voltage is zero with respect to the two piezoelectric vibrators 26a and 26b, (B) a state in which a positive voltage is applied, and (C) a state in which a negative voltage is applied.

Here, since the front end of the electric vibrator 2 6 b is fixed at the lower side, the front end of the piezoelectric vibrator 26a on the upper side is swung at an angle of about 2 times as compared with the case where a single piezoelectric vibrator is used. Therefore, the amplitude of the blade 21 shown in Fig. 1] can be further increased. In addition, the example of FIG. 13 is exemplified by a piezoelectric fan in which the opening portion 22 is formed in the blade 21, but the structure of the counterweight is attached to the front end of the blade 21 as shown in FIG. 9, or the blade 21 is as shown in FIG. Similarly, a piezoelectric fan having a curved structure is also applied. 0 «Seventh Embodiment FIG. 15 is a perspective view of a piezoelectric fan used in a cooling device according to a seventh embodiment. As shown in the figure, the piezoelectric fan 38 is formed by joining the blades 21 via the spacers 29 to the piezoelectric vibrating subunits having the E-shaped integral portions of the three piezoelectric vibrators 27a, 2, and 27c. In this example, the opening portion 22 is formed in the blade 2ι. Fig. 16 (AMC) is an illustration of the bending mode of the piezoelectric vibrating sub-unit portion of the aforementioned E-shape. 16(D) to (F) are diagrams showing the swing of the blade of the piezoelectric fan. The applied voltage (C) of the 27C is a negative electric current image 16 (A) with respect to the piezoelectric vibrator 27a. (2) The state when the voltage is applied to the positive voltage. (B) is the state when the positive voltage is applied. 134432.doc -19- 200930899 Here, since the front ends of the piezoelectric vibrators 27a and 27b are fixed, the pressure at the center The front end of the electric vibrator 27c swings at an angle of about 2 times as compared with the case of using a single piezoelectric vibrator. Therefore, the amplitude of the blade 21 shown in Fig. 15 can be further increased. The piezoelectric fan in which the opening portion 22 is formed in the blade 21 is exemplified, but the piezoelectric fan in which the weight is attached to the front end of the blade 21 as shown in Fig. 9 or the blade 21 is bent as shown in Fig. 11 The same applies to the "0" «Eighth Embodiment" Fig. 17 is a schematic view showing the configuration of a cooling device according to the eighth embodiment. The cooling device 101 is composed of a piezoelectric fan 31, a radiator 4, and a blower fan 50. In the embodiment of the eighth embodiment, the piezoelectric fan and the heat sink basically constitute a cooling device, and the piezoelectric fan The air in the space surrounded by the heat sink of the heat sink is swept to dissipate heat. However, in the example shown in FIG. 7, the air in the space formed by the heat sink 30 of the heat sink 40 is stirred by the piezoelectric fan 31. The fan fan 31 is configured to blow air as a whole to the outside by the blower fan 50. The piezoelectric fan 31 is constituted by the blade 21 forming the opening 22 and the piezoelectric vibrator 2A, and is basically the same as that shown in Fig. 3. In this example, the orientation of the blade 21 is inclined at about 45 〇c with respect to the longitudinal direction of the heat sink 30. Thereby, the support portion (fixed portion) of the electric vibrator 20 can be disposed outside the heat sink 40, and the piezoelectric fan The installation of 31 is easy to carry out. Further, the opening portion 22 increases the component opposed to the airflow by the blower fan 5, and can be closer to the simulation condition shown in Fig. 7(B), thereby improving the high temperature air of the heat sink 3 wall surface. 134432.doc .20· 200930899 In addition, the example of FIG. 17 is exemplified by the piezoelectric fan in which the opening 22 is formed in the blade 21, but the structure in which the weight is attached to the front end of the blade 21 as shown in FIG. 'Or the piezoelectric fan of the curved structure of the blade 21 as shown in Fig. 11 - "The ninth embodiment" - Fig. 18(A) is a perspective view showing a configuration of a cooling device according to a ninth embodiment, and Fig. 18(B) is a plan view of the piezoelectric fan. Fig. 18(B) As shown in the figure, the piezoelectric fan 39 includes a metal plate 19 in which a plurality of roots are integrated to project a plurality of blades 21. The opening 22 is formed in each of the blades 21. On the metal plate 19, the piezoelectric vibrator 25 is attached to the root of the blade 21. The metal plate 19 is attached to the support member 41 by the screw 42. By applying an alternating voltage to the piezoelectric vibrator 25, the metal plate 19 and the blade 21 are swung with the position of the support member 41 as a fulcrum. As shown in Fig. 18(A), the cooling device 102 is configured by arranging the piezoelectric fan 39 at a constant height (central height or slightly higher) than the bottom surface of the heat sink 40. The heat sink 40 is provided with a plurality of heat sinks 30 which are parallel to each other, and the piezoelectric fans 39 are arranged such that the blades 21 of the piezoelectric fans 39 are not slid against the heat sinks 30 between the adjacent heat sinks 30. In this manner, a cooling device 102 having a piezoelectric fan that swings a plurality of blades with a single piezoelectric vibrator is constructed. «10th Embodiment" Fig. 19 is a plan view of a piezoelectric fan according to a tenth embodiment. In the example of Fig. 19 (A), the metal plate 19 is divided into three regions of the left side [the central region C and the right region R, and the piezoelectric vibrator 25 [, 25C, 134432.doc -21 - 200930899 25R They are located in each area. Thereby, the (four) region can be independently swung. Similarly, in the example of Fig. 19(B), the metal plate 19 is divided into the left side region [the two regions of the right side of the ruler, and the piezoelectric vibrators 25L and 25R are provided in the respective regions. Thereby, the two regions can be independently swung. With this configuration, the blade turns of the respective regions can be swung according to the purpose. For example, in the case of Fig. 19(A), the piezoelectric vibrator 25 is driven by a reverse phase voltage by driving the piezoelectric vibrators η, 25R with a positive phase voltage (:, the reaction force of the supporting member can be reduced. Similarly, in the case of Fig. 19(B), # is driven by the piezoelectric vibrator 25L with a positive phase voltage, and the piezoelectric vibrator 25R' is driven with a reverse phase voltage to reduce the reaction force of the supporting member 41. The vibration of the member to which the support member 41 is attached is silenced. In addition, the number of divisions of the region or the number of blades in each region is not limited to those shown in Fig. 19, and the metal plate 19 and the blade 21 are vibrated as expected. Just set the mode as appropriate.

The position of each portion of the "heat sink", the piezoelectric fan, and the position of the opening formed in the blade is related to the cooling device and dimensional relationship described in the above embodiments. The extractor is large as a piezoelectric fan for the purpose of inserting a leaf between the fins of the heat sink. The blade scrapes off the hot air of the heat sink to promote cooling. In order to promote cooling, it is very important to increase the scraping area. Therefore, it is necessary to add heat to the surface area of the heat sink. It is also necessary to increase the amplitude of the sheet, and set the length of the heat sink between adjacent ones. .doc 22- 200930899 FIG. 20 is a plan view showing a state in which the blades 21 are disposed in the gap between the heat sinks 30 of the heat sink. Here, the X direction is referred to as the longitudinal direction, the y direction is the width direction, and the z direction is the thickness direction. e The parameter is intended to scrape the hot air on the surface of the fins 30, 30 by the blade 21, so the smaller the distance G between the fin 30 and the blade 21, the better. However, if the pitch g is narrowed, the air resistance when the blade 21 is swung will increase, and the amplitude of the blade 21 will decrease. On the other hand, in consideration of the air which scrapes off the surface of the heat sink 3 of the heat sink, it is not important to scrape the air at the central portion between the fins 30 (the area indicated by the symbol B in Fig. 20). Therefore, it is reasonable to provide the opening portion 22 at the center portion of the blade h in order to reduce the air resistance. If only the purpose of providing the opening portion 22 is emphasized, the opening portion 22 can be provided over the entire length of the blade 21. However, it can only be used for the blade for the following reasons. The central portion (the space indicated by symbol A in Fig. 2A) is provided with an opening portion. First, considering the root portion of the blade 21, since the amplitude of the root portion is small and the air resistance is small, there is no need to provide an opening portion. After considering the front end portion of the blade 21, there is no doubt that the blade 21 is not present in front of the front end, and the extruded air can be easily dispersed to the wide empty door. Therefore, the front end portion of the blade 21 is reduced in air resistance due to the opening portion. smaller. In addition, if an opening is formed at the end of the main sheet 21 of the Yiyi, it becomes thin and slender. 2 y benefits: u 丄&, the blade oscillates between the narrow fins. Although the resistance to work is reduced, it is saved, "/ The action of each blade is affected by the air, and the situation that the stable vibration cannot be formed is a rigid connection. In addition, the front end portion is suitable for storage, -6 " The heat between the heat sinks 30 is not integrated, and the influence on the air supply effect is large, and it is necessary to provide the air supply effect from the first two degrees. The amplitude of the front end is 134432.doc -23· 200930899 The opening portion is easy to form a direction. The flow of the air is stabilized. From these circumstances, it is preferable to provide the opening only in the central portion of the blade 21. The shape of the opening 22 is related to the longitudinal direction 'and the root portion and the front end portion for the reasons described below. In the wide range of openings, it is necessary to ensure that the size from the side of the longitudinal direction of the blade 21 to the side of the opening 22 of the side is greater than or equal to the width direction. ❹ ❹ From -Hit condition m 21 Original That is, the length is known, and the shape of the _ mouth (4) is also long. About the longitudinal dimension of the opening: If the end effect is ignored, the μ resistance of π to a certain position can be considered as 'speed. The square cross-sectional area is proportional to the ratio. That is, when the amplitude of h (x), the frequency is f, the cross-sectional area ratio Γα, then,

The air resistance of the 〇 2 2 2 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 In addition, '[cross-sectional area ratio] = ([blade width] _ [opening width]} / [interval between fins]. So 'the air resistance is proportional to the square of the amplitude, so the air near the root of the amplitude is small The resistance can be ignored. Therefore, it is basically meaningless to have an opening near the root. Regarding the front end, even if there is no opening, there is a large space at the front end of the opening. : This 'exhausted air, even if it does not pass through the blade 21 and the heat sink The narrow slit (part G in Fig. 20) can also flow toward the front end. Therefore, the air resistance is estimated to be small in view of the aforementioned end effect. The end effect is theoretically equivalent to the width of the blade 21. Therefore, it is necessary to provide an opening at least from the front end to I34432.doc •24·200930899 in the same length as the blade width. Even from the viewpoint of air resistance, there is no switch in the width direction of the opening:

, : According to the presence or absence of a piezoelectric fan, the difference in gradient with respect to the distance from the heat sink. The thick line does not have the situation of a piezoelectric fan, and there is a case of a piezoelectric fan. The temperature between the heat sink fins is shown by the thick line of the knife®21. Piezoelectric fan exists and operates Because the air at both ends of the blade is mixed, the temperature of the leaf 2 (the part of the symbol E in the figure) is uniform (the temperature gradient is gentle) as shown by the thin line in the figure. The gap between the junction of the fin and the blade (the portion of the symbol G in the figure) decreases, and the temperature gradient of the surface of the fin is steep. Since the heat flux and the temperature gradient become _', a large amount of heat flows out from the surface of the fin, that is, the cooling effect is improved. Due to this mechanism of cooling capacity improvement, if the temperature difference between the two ends of the blade (the position of G in Fig. 20 and the position of G+E) is insufficient, the cooling capacity cannot be sufficiently improved. Therefore, there is no doubt that it must be set in the area where the temperature changes greatly. The sides of the blade 2! should be as close as possible to the fins.) For the ruler phase, it is necessary to ensure that the temperature difference between the two ends is sufficient. If the distance from the heat sink 3G is relatively close, the temperature distribution becomes substantially straight. If the inclination of the straight line (=temperature gradient) is melted, the temperature of the surface of the heat sink is T〇, and the temperature from the wall surface of the heat sink to the size G is T〇+k*G, and the distance is (G+E). The temperature at the location is T〇+k*(G+E). Since the temperature at the position of the blade 21 is completely uniform, the temperature of the position of the blade 2ι is To k (G+E/2), so the temperature gradient can be estimated as ρ(丨+〇.5*Ε/〇). . 134432.doc -25- 200930899 That is, if E=G, it is expected to increase the cooling capacity by up to 5%. Considering that the temperature distribution of the blade portion cannot be completely uniformized, the temperature distribution may be deviated from the linear domain, and it is determined that E>G is effective in order to obtain a clear cooling capacity improvement. • «Other Embodiments> • In the above-described embodiments, the end portion of the piezoelectric vibrator is followed by the end of the blade to form a bimorph type piezoelectric fan, but the end of the blade may follow the piezoelectric The vibrator is comprehensive. Further, in the above-described embodiments, the example in which the end portion of the blade is attached to the weight is shown, but the weight may be integrally formed with the blade. Further, the weight may be provided not near the end of the blade but near the end. Further, in each of the embodiments shown above, a metal plate or a resin plate having a high elasticity such as phosphor bronze other than stainless steel may be used as the blade. Further, in the example other than the configuration shown in FIG. 12, the bimorph type piezoelectric vibrator is followed by one surface of the blade, but a single piezoelectric element is used as the piezoelectric vibrator following one surface of the blade. The piezoelectric element and the blade may constitute a unimorph type vibrator. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the configuration of a piezoelectric fan of Patent Document 1. Figure 2 is a schematic diagram showing the relationship between air resistance and amplitude of a piezoelectric fan. Fig. 3 is a perspective view of a piezoelectric fan used in the first embodiment of the "sorrowful" cooling device. 4(A) and 4(B) are schematic views showing the configuration of the same cooling device. Fig. 5 is a view showing the effect of the opening of the piezoelectric fan used in the cooling device of the first embodiment 134432.doc -26· 200930899. Figure 6 is a schematic illustration of the appearance of the airflow produced by the oscillation of the blades. Fig. 7 (A) and Fig. 7(B) are diagrams showing an example of the temperature distribution of the airflow flowing in the space between the fins in accordance with the presence or absence of the opening formed in the blade. Fig. 8 (4) and (B) are perspective views of an electric fan used in the cooling device of the second embodiment. Fig. 9 is a perspective view of a piezoelectric fan used in the cooling device of the third embodiment.

❷ Figure 10 is a schematic diagram showing the effect of the counterweight and the opening of the piezoelectric fan. Fig. 11 is a perspective view showing a piezoelectric fan used in the cooling device of the fourth embodiment. Side of the piezoelectric fan Fig. 12 is a plan view showing a cooling device according to the fifth embodiment. Fig. 13 is a perspective view showing a piezoelectric fan used in the cooling device of the sixth embodiment. Fig. 14 (AHC) is a schematic view showing a bending mode of the same piezoelectric fan. Fig. 15 is a perspective view showing the vertical image of the waste electric fan used in the cooling device of the seventh embodiment. Figs. 16(A)-(F) show the bending mode and the blade intention of the same piezoelectric fan. Figure 17 is a schematic view showing the configuration of a cooling device according to an eighth embodiment. 18(4) and (B) are schematic views showing the configuration of a cooling device according to a ninth embodiment. Figs. 19(4) and (B) are piezoelectric views of a cooling device used in a cooling device according to a tenth embodiment. 134432.doc -27· 200930899 A plan view of a fan. Figure 20 is a schematic view showing the relationship between the heat sink, the piezoelectric fan, and the opening formed in the blade. Figure 21 is a schematic diagram showing the difference in gradient with respect to the temperature of the heat sink depending on the presence or absence of the piezoelectric fan. [Description of main component symbols] Distance of the position of the part 19 20 > 25 ' 26 ' 27 20a, 20b Metal plate Piezoelectric vibrator Piezoelectric element

21 22 23 24 28, 29 30 31-39 40 41 50 100 , 101 110 120 Blade opening notch part weight spacer heat sink Piezo fan radiator support member air supply fan cooling heat generating circuit board 134432.doc - 28-

Claims (1)

200930899 X. Application for Patent Park: 1 · A cooling device, which is Taidong. Cover #知墩^. Piezoelectric fan, with piezoelectric vibrator according to voltage applied, followed by or integrated in the pressure a heat sink of a blade shunt fin that is oscillated by the piezoelectric vibrator; characterized in that: the blade 'is formed as a strip extending from the piezoelectric vibrator, and (4) arranging the piezoelectric vibrator and the vane at a position where the air is moved, and the opening or the notch is provided in the vane. 2. The cooling of the item 1 is as described in May. Installed, Ganshi Bazhong's description of the blade away from the aforementioned piezoelectric vibrator side of the & end or front end with a counterweight. 3. If § Qing seeking 1 or 2 cold; gp station -. The crucible device has a meandering shape in which the blade is twisted in the longitudinal direction. ❹ A cold heading device of the term 1 of the month, wherein the piezoelectric vibrator is configured to take the end of the j blade from both sides The piezoelectric vibrator and the aforementioned blade are configured as double pressure in a sandwiched configuration The cold-type device of the second aspect of the invention, wherein the piezoelectric vibrator is configured such that the end portion of the blade is sandwiched from both sides, and the piezoelectric vibrator and the blade are formed. In the case of a bimorph type resonator, the piezoelectric vibrator is configured such that the end portions of the vane are sandwiched from both sides, and the piezoelectric vibrator and the vane are formed. A bimorph type vibrator. 7. A cooling device according to item 1, wherein a space for generating a flowing air flow is disposed in a space between the fins. 134432.doc 200930899 The space between the heat sinks is as described above. The space between the heat sinks is between the heat sinks and the space between the heat sinks in the space between the heat sinks. 8. The cooling device of claim 2, wherein a fan for generating a flowing air flow is provided. The cooling unit is provided with a fan that generates a flowing airflow. 10. The cooling device of claim 4, wherein a fan that generates a flowing airflow is provided. ❹ ❹ Π. The cooling device of claim 5, wherein A fan for generating a flowing air flow is provided. 12. The cooling device of claim 6, wherein a fan for generating a flowing air flow is provided. Set:: 1 'I: .4, 5, 7, 8, 1 and any cooling The shape of the opening is the edge of the elongated portion along the length of the blade; the edge of the blade is parallel to the opening parallel to the edge, and the distance between the fin and the blade is The cooling device of claim 3, wherein the opening portion has a long shape along the direction of the blade, and the side of the opening is parallel to the side of the blade from the longitudinal direction of the blade. The size is larger than the gap between the heat sink and the blade. [15] The cooling device of claim 6, wherein the opening portion is longer than the blade from the side in the longitudinal direction of the blade to the side of the opening portion of the blade, and is larger than the heat sink and the heat sink. The gap between the blades is large. (1) The cooling device of the item 9 wherein the opening portion has a long shape along the longitudinal direction of the blade 134432.doc 200930899, and the size of the gap between the blades is defined by the dimension of the side of the opening parallel to the side of the blade Big. The cooling device according to claim 12, wherein the longitudinal direction of the front portion is a long shape, and a size of a gap between the blades is larger than a dimension of a side of the opening portion in which the side of the blade is parallel. The side of the length direction of the crucible is closer to the side than the heat sink and the front opening along the length direction of the vane to the front side of the heat sink and the front 134432.doc