JP2007162525A - Jet generating device, heat radiating device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jet generating device or the like capable of reducing noise due to turbulence of air current of composite jet. <P>SOLUTION: The closer a vibration plate 3 is positioned, the more turbulence of air current due to vibration of the vibration plate 3 should exist. Because flow of air flowing in and out via ducts 2a, 2b, and the vibrating vibration plate 3 interfere. Such turbulence of air current becomes one of causes of noise. However, the ducts 2a, 2b are arranged roughly in parallel with a vibration direction R. Consequently, air current via the ducts 2a, 2b near the vibration plate 3 interferes with the vibrating vibration plate 3 but air current via the ducts 2a, 2b remote from the vibration plate 3 does nit interferes with the vibrating vibration plate 3. Consequently, noise can be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a jet generating device that generates a synthetic jet of gas, a heat radiating device in which the jet generating device is incorporated, and an electronic apparatus in which the heat radiating device is mounted.

  Conventionally, an increase in the amount of heat generated from a heating element such as an IC (Integrated Circuit) associated with high performance of a PC (Personal Computer) has been a problem, and various heat radiation technologies have been proposed or commercialized. Yes.

  As a heat dissipation method, a composite jet is generated by discharging air in a pulsating flow, and this combined jet is supplied to a heat dissipation fin (heat sink), etc., and the temperature boundary layer formed on the surface of the heat dissipation fin is efficient. There is a method of well destroying and dissipating heat (see, for example, Patent Document 1). Such a jet generating device has a housing having an opening and a diaphragm that causes a pressure change in the air in the housing. When the diaphragm vibrates, a pressure change occurs in the casing, and air is discharged as a pulsating flow through the opening, thereby generating a synthetic jet.

The synthetic jet is generated according to the following principle. As air flows when air is discharged from the opening of the housing, the air pressure around the opening outside the housing is reduced, so that the surrounding air is caught in the air discharged from the opening. A synthetic jet is generated.
Japanese Patent Laying-Open No. 2005-256834 (paragraph [0079], FIG. 1)

  By the way, since the jet generating device that generates the synthetic jet discharges the gas as a pulsating flow, when the gas is discharged, the air flow is disturbed in the housing or in the vicinity of the gas discharge opening, and the air flow sound may become noise. is there.

  In view of the circumstances as described above, an object of the present invention is to provide a jet flow generating device capable of reducing such noise, a heat radiating device in which the jet flow generating device is incorporated, and an electronic apparatus in which the heat radiating device is mounted. There is to do.

  In order to achieve the above object, a jet flow generating apparatus according to the present invention has a vibrating body and a gas flow path communicating between the inside and the outside, the gas is contained in the inside, and the vibration is caused by the vibration of the vibrating body. A housing configured to discharge the gas as a pulsating flow through the flow path to the outside and to suppress the turbulence of the air flow when the vibrating body vibrates by applying a pressure change to the gas; It comprises.

  In the present invention, since the casing is configured to suppress the turbulence of the airflow when the vibrating body vibrates, noise can be reduced.

  “Inside” and “outside” are inside and outside of the “housing”.

  In the present invention, an opening formed in the housing may constitute a flow path, or a nozzle provided in the housing may constitute a flow path.

  Examples of the “gas” include air, but are not limited thereto, and may be nitrogen, helium gas, argon gas, or other gas.

  In the present invention, the flow path has a quadratic or oval cross section that is substantially perpendicular to the direction in which the gas is discharged. Thus, since the flow path has a curve on the inner surface, the turbulence of the air flow in the flow path can be suppressed. “Cubic curve shape” means a circle, an ellipse, a parabola, or a hyperbola. The parabola, the hyperbola, and the like may be, for example, a parabola or a curve obtained by combining the hyperbola. In addition, the “quadratic curve shape” referred to in the present invention includes a curve in which at least two of these circles, ellipses, parabolas and hyperbolas are combined. The “oval shape” is a shape in which a circle or an ellipse is combined with a straight line and has no corners. In particular, by adopting an oval shape, the cross-sectional area can be increased as compared with, for example, a circular cross-section flow path, and noise can be reduced by reducing the velocity of the gas flowing through the flow path.

  In the present invention, a plurality of the flow paths are arranged substantially parallel to the vibration direction of the vibrating body. It is considered that the airflow turbulence due to the vibration of the vibrating body increases as the flow path is closer to the vibrating body. Therefore, according to the configuration of the present invention, the turbulence of the airflow is reduced in the channel far from the vibrating body.

  In the present invention, the housing includes a flow channel wall surface forming the flow channel and an inner wall surface connected to the flow channel wall surface at an angle larger than 90 degrees. As a result, the airflow smoothly flows on the inner wall surface and the channel wall surface.

  In the present invention, the casing has an inner wall surface having a curved surface. Thereby, the airflow in a housing | casing becomes smooth and can suppress turbulence of an airflow. The curved surface may be anywhere as long as it is an inner wall surface of the housing.

  In the present invention, the casing has a channel wall surface that forms the channel, and the curved surface is provided so as to connect the inner wall surface and the channel wall surface. Thereby, an airflow comes to flow smoothly through an inner wall surface, a curved surface, and a flow path wall surface.

  The heat dissipating device according to the present invention includes a heating element, a vibrating body, and a flow path, gas is contained therein, and a pressure change is given to the gas by the vibrating body. A housing configured to discharge the gas as a pulsating flow toward the heating element and to suppress the turbulence of the air flow when the vibrating body vibrates.

  In the present invention, the heating element is a heat sink having a plurality of fins at a predetermined interval in the arrangement direction of the flow paths, and the flow path has a width narrower than the predetermined interval in the arrangement direction. Thereby, it can avoid that the gas discharged from the flow path collides with the end surface of each fin of a heat sink. That is, when the air current collides with the end of each fin, the air current is disturbed in the vicinity of the end face, but such a situation can be avoided in the present invention.

  In the present invention, each fin has an envelope surface on the side where the housing is disposed, and the flow path has an end portion in contact with the envelope surface. Even with such a configuration, it is possible to prevent the airflow from colliding with the end surfaces of the fins and to suppress the turbulence of the airflow.

  In the present invention, the heat dissipation device further includes a plurality of nozzles each having an end portion for guiding the gas discharged from each flow path to the outside, and each end portion of the nozzle includes the fins. It is arranged to be inserted between. Thereby, it is possible to reliably avoid the gas discharged from the flow path as described above from colliding with the end of each fin of the heat sink.

  A heat radiating device according to another aspect of the present invention includes a heating element, a vibrating body, and a flow path, and a gas is contained therein, and a pressure change is applied to the gas by the vibrating body. A casing in which the position of the flow path with respect to the heating element is set so as to discharge the gas as a pulsating flow toward the heating element through a path and suppress the turbulence of the air flow when the gas is discharged; It comprises. Specifically, as described above, the flow path has a width narrower than the predetermined interval in the arrangement direction of the fins, or in addition to such a condition, the end of the flow path has an envelope surface. Or the end of the channel may be disposed so as to be inserted between the fins.

  An electronic apparatus according to the present invention includes a heat source, a heat radiating member thermally connected to the heat source, a vibrating body, and a flow path, and a gas is contained therein. A casing configured to discharge the gas as a pulsating flow toward the heat radiating member through the flow path and to suppress the turbulence of the air flow when the vibrating body vibrates by being given a pressure change. It comprises.

  The term “thermally connected” means that they are in direct contact with each other or are connected through a heat conductive member or a heat conductive sheet-like member, such as gas or liquid. It is not included in the case of conducting heat by the fluid.

  An electronic apparatus according to another aspect of the present invention includes a heat generation source, a heat dissipation member thermally connected to the heat generation source, a vibration body, and a flow path. The pressure change is applied to the gas by the gas, so that the gas is discharged as a pulsating flow toward the heat radiating member through the flow path, and the heat dissipation is suppressed so as to suppress the turbulence of the air flow when the gas is discharged. A housing in which the position of the flow path with respect to the member is set.

  As described above, according to the present invention, it is possible to reduce the noise caused by the turbulence of the airflow of the jet generating device that generates the composite jet.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a heat dissipation device according to an embodiment of the present invention.

  The heat dissipating device 100 includes a heat sink 60 as a heating element and a jet generating device 10 that generates this synthetic jet and supplies it to the heat sink 60. The heat sink 60 has a plurality of heat radiating fins 60a, and the plurality of heat radiating fins 60a are arranged at predetermined intervals. An IC such as a processor (not shown) is thermally connected to the heat sink 60 as a heat source. The heat source is not limited to an IC, and may be any other electronic component such as a resistor, a motor, or the like, as long as it generates heat by itself.

  FIG. 2 is a cross-sectional view showing the jet flow generating device 10. 3 is a cross-sectional view taken along line AA in FIG. FIG. 4 is a front view of the heat dissipation device 100 as viewed from the heat sink 60 side.

  The jet generating device 10 includes a housing 1 containing air inside, and a nozzle body 2 attached to the front surface 1a of the housing 1. An opening 1 c is formed in the front surface 1 a of the housing 1. A plurality of air flow paths 2a and 2b are formed in the nozzle body 2, and the inside and outside of the housing 1 communicate with each other through these flow paths 2a and 2b. The flow paths 2 a and 2 b are arranged in the longitudinal direction (X direction) of the casing 1 and the nozzle body 2. The flow paths 2a and 2b have a circular cross section in the direction in which air is discharged (Y direction). Thus, since the flow paths 2a and 2b have curves on the inner surfaces, the turbulence of the air flow in the flow paths 2a and 2b can be suppressed and noise is reduced as compared with the case where the inner surfaces have corners. The cross sections of the flow paths 2a and 2b are not limited to a circle, but may be other quadratic curves such as an ellipse, a parabola, or a hyperbola. Alternatively, a combination of at least two of these may be used. Alternatively, as described later, an oval shape in which a circle or an ellipse and a straight line are combined may be used.

  In addition, although the housing | casing 1 and the nozzle body 2 were set as the different bodies, both may be integral. That is, the housing 1 may have a configuration in which a plurality of holes (flow paths) that communicate the inside and outside of the housing 1 are provided.

  In the housing 1, there are provided a diaphragm 3 as a vibrating body, an elastic support member 6 provided around the diaphragm 3 to support the diaphragm 3 so as to vibrate, and a drive device 5 for driving the diaphragm 3. Yes. The elastic support member 6 is attached to the inner wall 1d (see FIG. 2) of the housing 1, for example. Although the diaphragm 3 has a plate shape, it is not limited to a plate shape. Two chambers 16 and 17 are formed in the housing 1 by the diaphragm 3 and the elastic support member 6. In FIG. 3, the chamber 16 on the left side of the diaphragm 3 communicates with the outside through the flow path 2a. The chamber 17 on the right side of the diaphragm 3 communicates with the outside through the flow path 2b.

  The driving device 5 is disposed in the approximate center of the housing 1 in the X direction. The drive device 5 is, for example, an electromagnetic drive type drive device. Specifically, the driving device 5 is configured by arranging two magnets 11 and 12 sandwiching a plate-like yoke 13 in a main yoke 14 facing the yokes 7 and 9. The plate yoke 13 and the magnets 11 and 12 may be formed in a disk shape or a polygonal plate shape. A coil 8 is wound around the plate yoke 13, and is fixed to the coil 8 approximately at the center of the diaphragm 3. For example, the coil 8 may be wound around a coil bobbin (not shown), and the diaphragm 3 may be fixed to the coil bobbin. A magnetic circuit is formed by the main yoke 14, the plate yoke 13, and the magnets 11 and 12, and when the coil 8 is energized, the diaphragm 3 vibrates in the R direction (X direction).

  Although the drive device 5 is an electromagnetic drive type, the drive device 5 is not limited to this and may be a piezoelectric drive type or an electrostatic drive type. In the case of piezoelectric driving, the diaphragm 3 itself becomes a piezoelectric actuator, and a reduction in size is expected.

  The housing 1 is made of, for example, resin, rubber, or metal. Resin and rubber are easy to produce by molding and are suitable for mass production. In addition, when the housing 1 is made of resin or rubber, it is possible to suppress sound generated by driving the driving device 5 or airflow sound generated by vibration of the diaphragm 3. That is, when the housing 1 is made of resin or rubber, the attenuation rate of those sounds also increases, and noise can be suppressed. Furthermore, it can respond to weight reduction and becomes low-cost. When the housing 1 is manufactured by injection molding of resin or the like, it can be molded integrally with the nozzle body 2.

  When the housing 1 is made of a material having high thermal conductivity, for example, metal, heat generated from the driving device 5 can be released to the housing 1 and radiated to the outside of the housing 1. Examples of the metal include aluminum and copper. When considering thermal conductivity, carbon is not limited to metal. As the metal, magnesium that can be injection-molded can be used.

  The operation of the jet flow generating device 10 configured as described above will be described.

  For example, when a sinusoidal AC voltage is applied to the driving device 5, the diaphragm 3 performs sinusoidal vibration. Thereby, the volume in the chambers 16 and 17 increases or decreases. As the volumes of the chambers 16 and 17 change, the pressures in the chambers 16 and 17 change, and accordingly, an air flow is generated as a pulsating flow through the flow paths 162a and 2b, respectively. For example, when the diaphragm 3 is displaced in a direction that increases the volume of the chamber 16, the pressure in the chamber 16 decreases and the pressure in the chamber 17 increases. Thereby, the air outside the housing 1 flows into the chamber 16 through the flow path 2a, and the air in the chamber 17 is discharged to the outside through the flow path 2b. On the contrary, when the vibrating body 3 is displaced in the direction of decreasing the volume of the chamber 16, the pressure in the chamber 16 increases and the pressure in the chamber 17 decreases. Thereby, the air in the chamber 16 is ejected to the outside through the flow path 2a, and the external air flows into the chamber 17 through the flow path 2b. When air is discharged from the flow paths 2a and 2b, the air pressure around the flow paths 2a and 2b decreases, so that the surrounding air is entrained in the air ejected from each flow path and a synthetic jet is generated. . The synthetic jet is blown onto the heat sink 60, whereby the heat sink 60 is dissipated.

  On the other hand, when air is discharged from the flow paths 2a and 2b, noise due to vibration of the diaphragm 3 is generated independently of the flow paths 2a and 2b. However, since each sound wave generated in each flow path 2a and each flow path 2b is a sound wave having an opposite phase, it is weakened. As a result, noise is suppressed, and noise reduction can be achieved.

  Here, in such a jet generating device 10, it is considered that the turbulence of the air flow due to the vibration of the diaphragm 3 increases as the position is closer to the diaphragm 3. This is because the flow of air flowing in and out through the flow paths 2a and 2b interferes with the vibrating diaphragm 3. Such disturbance of the airflow is one of the causes of noise. However, in the present embodiment, the flow paths 2a and 2b are arranged substantially parallel to the vibration direction R. Therefore, the airflow through the flow paths 2 a and 2 b close to the vibration plate 3 interferes with the vibrating vibration plate 3, but the airflow through the flow paths 2 a and 2 b away from the vibration plate 3 does not interfere with the vibration plate 3. Considering the amplitude of the diaphragm 3 (the width between the left and right dead points of the diaphragm 3 indicated by the one-dot chain line in FIG. 3), the airflow in most of the channels 2a and 2b is oscillated. Does not interfere with the vibrating plate 3. Thereby, noise can be reduced.

  In the present embodiment, the driving device 5 is disposed in the approximate center of the housing 1 in the X direction (vibration direction R), and the two magnets 11 and 12 are symmetrical with respect to the vibration direction R of the diaphragm 3. The main yoke 14 also has a symmetrical structure with respect to the vibration direction R. Therefore, when the diaphragm 3 vibrates and discharges air through the nozzle body 2 as will be described later, the amount of air discharged from the chamber 16 and the amount of air discharged from the chamber 17 should be substantially the same. Can do. This contributes to noise reduction. Furthermore, since the drive device 5 has a symmetrical structure with respect to the vibration direction R of the diaphragm 3, the state of the airflow in the chambers 16 and 17 is also symmetric with respect to the diaphragm 3, contributing to noise reduction.

  The configuration of the drive device 5 does not necessarily have a symmetrical structure, and is not limited to the configuration shown in FIG. For example, any one of the magnets 11 and 12 may be provided. In that case, any one of the yokes 7 and 9 may be provided. Alternatively, two electromagnetic drive devices 5 may be arranged on both sides of the diaphragm 3, that is, on the chambers 16 and 17, respectively.

  In the present embodiment, as shown in FIGS. 4 and 5, the width t in the arrangement direction (X direction) of each of the flow paths 2a and 2b is formed to be narrower than the interval u between the heat radiation fins 60a. preferable. The width of the airflow 18 discharged from the flow paths 2a and 2b increases as the airflow 18 moves toward the radiation fins 60a. Here, under the above condition of u> t, the distance s between the end portions 2c of the flow paths 2a and 2b and the end face 60b of the radiating fin 60a should be set to about s ≦ (1/2) t. Accordingly, it is possible to avoid the airflow 18 from colliding with the end surface 60b of the heat radiation fin 60a as shown in FIG. In FIG. 6, the turbulence of the airflow is generated in the vicinity of the end surface 60b of the radiating fin 60a. For example, in FIGS. 4 and 5, if t is 1 to 2 mm, s is preferably 0.5 to 1.0 mm.

  Here, as shown in FIGS. 7A and 7B, for example, when the horizontally long flow path 21a is provided in the casing 21 of the jet flow generating device, the air flow discharged from the flow path 21a is radiated by the heat flow. Since it collides with the end surface 60b of the fin 60a, the airflow is disturbed near the end surface 60b and noise is generated. Further, as shown in FIGS. 8A and 8B, the width of the flow path 31a is the interval between the heat radiating fins 60a even if a plurality of flow paths 31a are provided in the casing 31. Greater than. Therefore, in this case as well, as shown in FIG. 9, the air flow discharged from the flow path 31a collides with the end surface 60b of each radiating fin 60a, so that the air flow is disturbed near the end surface 60b and noise is generated. Therefore, as shown in FIG. 4 and FIG. 5 described above, u> t is satisfied as much as possible, and the end portions of the flow paths 2a and 2b are disposed as close as possible to the end surface 60b of the radiation fin 60a. preferable.

  Alternatively, as shown in FIG. 10, the nozzle body 2 may be set in contact with the end surface 60 b of the radiating fin 60 a, that is, the end portions of the flow paths 2 a and 2 b may be in contact with the envelope surface 60 c of the heat sink 60. . In addition, as shown in FIG. 11, the nozzle 41 a having the flow path 41 b is provided in the casing 41 of the jet flow generating device, and the nozzle 41 a is disposed so as to be inserted between the radiation fins 60 a. Is also possible. According to the configuration shown in FIGS. 10 and 11, it is possible to reliably avoid the air current from colliding with the end surface 60 b and to reduce noise.

  12 and 13 are front views of a heat dissipation device according to still another embodiment. As shown in FIG. 12, a plurality of flow paths 25 a having an oval cross section as described above are arranged in the casing 25 of the jet flow generating device 30 in the vibration direction (lateral direction in the figure) of a diaphragm (not shown). It may be. By adopting an oval shape, for example, the cross-sectional area can be increased compared to a circular cross-section flow path, and noise can be reduced by reducing the velocity of the gas flowing through the flow path.

  Alternatively, as shown in FIG. 13, a plurality of flow paths 35 a provided in two upper and lower stages are arranged in the casing 35 of the jet flow generating device 40 in the vibration direction (lateral direction in the figure) of a diaphragm (not shown). Also good. Also in this case, since the total sum of the cross-sectional areas of the flow passages increases, the flow rate of the air becomes small and noise can be reduced if the total discharge amount of air per unit time is the same.

  FIG. 14 is a perspective view showing a jet flow generating device according to still another embodiment. FIG. 15 is a cross-sectional view taken along the broken line F shown in FIG.

  On the front surface 51a of the casing 51 of the jet flow generating device 50, an air flow path 52 is provided on the upper side, and a flow path 53 is provided on the lower side. The inside of the housing 51 is divided into two by the diaphragm 33 disposed in the housing 51 and the elastic support member 36 that supports the diaphragm 33. Thereby, chambers 54 and 55 are formed in the housing 51. The chambers 54 and 55 communicate with the outside of the housing 51 through flow paths 52 and 53, respectively.

  In addition, the flow path 52 or 53 is not a long shape as shown in the figure, but in a form in which a plurality of holes (flow paths) are provided as shown in FIG. 1 to FIG. 6, FIG. 12, FIG. There may be. In that case, the flow path and the radiating fins 60a of the heat sink 60 satisfy various relationships, for example, satisfy the relationship u> t or satisfy the relationship shown in FIGS.

  A driving device 45 for driving the diaphragm 33 is disposed on the upper portion of the housing 51. For example, a magnet 27 magnetized in a substantially vertical direction (Z direction in FIG. 15) is incorporated inside a cylindrical yoke 26, and a disc-shaped yoke 34 is attached to the magnet 27. The magnet 27 and the yokes 26 and 34 constitute a magnetic circuit. A coil bobbin 29 around which a coil 28 is wound enters and leaves the space between the magnet 27 and the yoke 26. The coil bobbin 29 is fixed to the surface of the diaphragm 33. The driving device 45 can vibrate the diaphragm 33 in the direction of arrow R.

  The flow path 52 is formed by a flow path wall surface 51b. Inside the casing 51, inner wall surfaces (slopes) 51c and 51d connected to the flow path wall surface 51b at an angle α larger than 90 degrees are provided. The slopes 51c and 51d are provided so as to extend along the X direction. The angle α only needs to be larger than 90 degrees and can be arbitrarily set. Slopes 51c and 51d having the same configuration are also provided on the side where the flow path 53 is provided. The angle between the slope 51d and the channel wall surface 51b may be α, or may be an angle different from α and greater than 90 degrees.

  In the jet flow generating device 50 configured as described above, the vibration plate 33 vibrates in the Z direction (R direction) by driving the driving device 45. As a result, the volumes of the chambers 54 and 55 alternately increase or decrease, that is, a pressure change occurs, and air is alternately discharged as a pulsating flow through the flow paths 52 and 53.

  In the present embodiment, since the slopes 51c and 51d connected to the flow path wall surface 51b are provided, the airflow smoothly flows along the slopes 51c and 51d. That is, the airflow can be prevented from being disturbed in the vicinity of the flow paths 52 and 53 in the housing 51, and noise is reduced.

  16 is a cross-sectional view taken along line BB in FIG. As described above, the slope connected to the channel wall surface 51b may be provided with the slope 51e extending in the Z direction as well as the slopes 51c and 51d extending in the X direction shown in FIG.

  FIG. 17 is a cross-sectional view showing a modification of the jet generating device shown in FIG. The casing 61 of this jet flow generating device is provided with flow paths 62 and 63 in two upper and lower stages. The channel 62 is formed by the channel wall surface 61b, and curved surfaces 61f and 61g are formed between the channel wall surface 61b and the inclined surface 61c. Similarly, curved surfaces 61f and 61g are formed on the side where the flow path 63 is provided. As a result, the air smoothly flows on the slope 61c (61d), the curved surface 61f (61g), and the flow path wall surface 61b, and noise is reduced. In the present embodiment, the curved surface 61h is also formed on the surface connecting the ceiling surface or floor surface to the inclined surface 61c.

  In the form shown in FIG. 17 as well, the curved surface may be formed when viewed in the Z direction, as in the case described in FIG.

  FIG. 18 is a cross-sectional view showing a modification of the jet flow generating device shown in FIG. The inner wall surface of the casing 71 of the jet flow generating device has a ceiling surface 71a, a vertical wall surface 71b, and a curved surface 71d connecting them. The inner wall surface of the housing 71 has a floor surface 71c, and further has a curved surface 71e that connects the floor surface 71c and the vertical wall surface 71b. By providing the curved surfaces 71d and 71e as described above, the airflow in the casing 71 becomes smooth and noise is reduced.

  In the form shown in FIG. 18 as well, the curved surface may be formed when viewed in the Z direction, as in the case described in FIG.

  15, 17, and 18 show a mode in which the casings 51, 61, 71 are opened to form the flow path 52, etc., but as described above, the nozzle body separate from the casing (FIG. (Refer to 1, 2, etc.), a slope and a curved surface may be formed.

  FIG. 19 is a perspective view illustrating a state where the above-described heat dissipation device 100 and the like are mounted on the PC 200 as an electronic device. The synthetic jet supplied from the jet generating device 10 is blown to the heat sink 60, and air with heat is discharged from the exhaust port 37 of the PC housing provided behind the heat sink 60.

  As an example of the electronic device in FIG. 19, a laptop PC is given as an example. However, the electronic device may be a desktop PC. Not only a PC but also a PDA (Personal Digital Assistance), an electronic dictionary, a camera, a display device, an audio / visual device, a projector, a mobile phone, a game device, a car navigation device, a robot device, and other electrical appliances.

  The heating element is not limited to a heat sink, and includes, for example, electronic components such as an IC, a coil, and a resistor. Any heating element may be used.

It is a perspective view which shows the thermal radiation apparatus which concerns on one embodiment of this invention. It is sectional drawing of the jet flow generator shown in FIG. It is the sectional view on the AA line in FIG. It is the front view seen from the heat sink side of the heat radiating device. It is a figure for demonstrating the relationship between the width | variety of a flow path, and the space | interval of a radiation fin. It is a figure which shows a mode that the disturbance of airflow has generate | occur | produced in the end surface vicinity of a radiation fin. It is a figure which shows a mode that the turbulence of airflow has generate | occur | produced in the end surface vicinity of a radiation fin, when a horizontally long flow path is provided. It is a figure which shows a mode that the turbulence of airflow has generate | occur | produced in the end surface vicinity of the radiation fin similarly to FIG. It is a top view of the jet flow generator shown in FIG. 8, and a radiation fin. It is a top view which shows a part of heat radiator which concerns on other embodiment of this invention, and is a figure which shows the form which the nozzle body contact | connected to the end surface of a radiation fin. It is a top view which shows a part of thermal radiation apparatus which concerns on another embodiment of this invention, and is a figure which shows the form arrange | positioned so that a nozzle may be inserted between each thermal radiation fin. It is a front view of the heat radiator which concerns on another embodiment of this invention, and is a figure which shows the form which the cross section of a flow path becomes an ellipse shape. It is a front view of the heat radiator which concerns on another embodiment of this invention, and is a figure which shows the form provided with the upper and lower two steps of flow paths. It is a perspective view which shows the jet flow generator which concerns on another embodiment. It is sectional drawing of the broken-line part shown in FIG. It is the BB sectional view taken on the line in FIG. It is sectional drawing which shows the modification of the jet flow generator shown in FIG. It is sectional drawing which shows the modification of the jet flow generator shown in FIG. It is a perspective view which shows the state with which the heat radiator etc. which were mentioned above were mounted in PC as an electronic device.

Explanation of symbols

1, 2, 31, 35, 41, 51, 61, 71 ... casing 2 ... nozzle body 2a, 2b, 25a, 31a, 52, 53, 62, 63 ... flow path 3, 33 ... diaphragm 5, 45 ... Drive device 10, 30, 40, 50 ... Jet generator 51b, 61b ... Channel wall surface 51c, 51d, 51e ... Slope (inner wall surface)
60 ... Heat sink 60a ... Heat radiation fin 60b ... End face 60c ... Envelope surface 61f, 61g, 71d, 71e ... Curved surface 100 ... Heat dissipation device 200 ... PC

Claims (13)

A vibrating body,
A gas flow path communicating between the inside and the outside; the gas is contained in the inside; and pressure change is applied to the gas by vibration of the vibrating body, whereby the gas is pulsated through the flow path. And a casing configured to suppress turbulence of the air flow when the vibrating body vibrates as a flow. The jet generator according to claim 1,
The flow path has a quadratic or oval cross section substantially perpendicular to the direction in which the gas is discharged. The jet generator according to claim 1,
A plurality of the flow paths are arranged substantially parallel to the vibration direction of the vibrating body. The jet generator according to claim 1,
The housing is
A channel wall surface forming the channel;
And an inner wall surface connected to the flow path wall surface at an angle larger than 90 degrees. The jet generator according to claim 1,
The casing has an inner wall surface having a curved surface. The jet generator according to claim 5,
The housing has a channel wall surface forming the channel,
The jet generator according to claim 1, wherein the curved surface is provided so as to connect the inner wall surface and the channel wall surface. A heating element;
A vibrating body,
Having a flow path, containing gas therein, and changing the pressure of the gas by the vibrating body, the gas is discharged as a pulsating flow toward the heating element through the flow path, And a housing configured to suppress turbulence of the airflow when the vibrating body vibrates. The heat dissipating device according to claim 7,
The heating element is a heat sink having a plurality of fins at predetermined intervals in the arrangement direction of the flow paths,
The heat dissipation device, wherein the flow path has a width narrower than the predetermined interval in the arrangement direction. The heat dissipating device according to claim 8,
Each of the fins has an envelope surface on the side where the housing is disposed,
The heat dissipation device, wherein the flow path has an end portion in contact with the envelope surface. The heat dissipating device according to claim 8,
A plurality of nozzles each having an end portion for guiding the gas discharged from each flow path to the outside;
Each said nozzle is arrange | positioned so that the said edge part may be inserted between each said fin, The heat radiator characterized by the above-mentioned. A heating element;
A vibrating body,
Having a flow path, containing gas therein, and changing the pressure of the gas by the vibrating body, the gas is discharged as a pulsating flow toward the heating element through the flow path, And a housing in which the position of the flow path with respect to the heating element is set so as to suppress the turbulence of the air flow when the gas is discharged. A heat source,
A heat dissipating member thermally connected to the heat source;
A vibrating body,
Having a flow path, containing gas therein, and changing the pressure of the gas by the vibrating body, discharging the gas as a pulsating flow toward the heat radiating member through the flow path, An electronic device comprising: a housing configured to suppress turbulence of an air flow when the vibrating body vibrates. A heat source,
A heat dissipating member thermally connected to the heat source;
A vibrating body,
Having a flow path, containing gas therein, and changing the pressure of the gas by the vibrating body, discharging the gas as a pulsating flow toward the heat radiating member through the flow path, An electronic device comprising: a housing in which a position of the flow path with respect to the heat radiating member is set so as to suppress disturbance of an air flow when gas is discharged.

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