Heat Sink Structure of Audio Equipment

Abstract

To provide a heat sink structure that suppresses resonance of heat dissipation fins in a configuration that is easy to manufacture.SOLUTION: A heat sink structure used for acoustic equipment has a base portion, and a plurality of plate-shaped heat radiation fins erected on a predetermined surface of said base portion in a first direction orthogonal to the predetermined surface, and arranged in a second direction orthogonal to the first direction, and in a cross-section parallel to the first and second directions of the heat radiation fins, the slope of the side surface with respect to the base portion is different between adjacent heat radiation fins in the second direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a heat sink structure for audio equipment.

Background Art

[0002] When audio equipment is in use, heat is generated from electronic components such as power ICs and regulators. Therefore, a heat sink may be provided directly on these components or on the housing that houses these components. This heat sink has, for example, a plurality of heat radiation fins arranged in parallel so as to have a large surface area, and heat is released from these heat radiation fins to the outside air. Thus, when a heat sink with heat radiation fins arranged in parallel is provided in audio equipment, these heat radiation fins may resonate and vibrate at a specific frequency like a tuning fork. When this vibration is transmitted to a circuit that handles an acoustic signal, elements such as electronic components and wiring materials that make up the circuit are vibrated. As a result, factors such as contact resistance and induced voltage in these elements change, and noise may be added to the acoustic signal or the acoustic signal may be distorted, which becomes a cause of deterioration in sound quality.

[0003] Patent Document 1 describes that by forming ribs at different positions of each of a plurality of fins, fins having the same natural vibration frequency are eliminated and resonance is suppressed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] As in Patent Document 1, by forming ribs on each of a plurality of fins to make the widths of the fins partially different, that is, by adopting a configuration in which the rib portions protrude in the width direction, the shape of each fin becomes complicated. For example, it becomes difficult to manufacture a heat sink by casting, and there is a problem that manufacturing constraints occur.

[0006] An object of the present invention is to provide a heat sink structure that suppresses resonance of heat radiation fins with a configuration that is easy to manufacture.

Means for Solving the Problems

[0007] In order to solve the above problems, a heat sink structure for an acoustic device according to the present invention is a heat sink structure used for an acoustic device, a base portion, plate-like heat radiation fins erected in a first direction orthogonal to a predetermined surface of the base portion, and a plurality of the heat radiation fins arranged in parallel in a second direction orthogonal to the first direction, and in a cross section of the heat radiation fin parallel to the first direction and the second direction, the inclination of the side surface with respect to the base portion is made different between adjacent heat radiation fins in the second direction.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a heat sink structure that suppresses resonance of heat radiation fins with a configuration that is easy to manufacture.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of a housing to which the heat sink structure according to this embodiment is applied, FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1, and FIG. 3 is a plan view showing the heat sink structure according to this embodiment. In FIGS. 1 to 3, the X-axis indicates the width direction, the Y-axis indicates the height direction, and the Z-axis indicates the front-rear direction. These directions are shown for convenience of explanation, and the plate material structure of this embodiment is not limited to being arranged in the directions shown in the figures.

[0011] The heat sink structure 1 according to this embodiment is applied to the audio amplifier 100. Specifically, as shown in FIG. 1, the heat sink structure 1 is provided on the housing 110 of the audio amplifier 100. The heat sink structure 1 includes a base portion 10 and a plurality of heat radiation fins 20 erected on the base portion 10.

[0012] The base portion 10 constitutes a part of the housing 110 and is a generally plate-shaped member extending in the X-Z direction. It has a lower surface 11 located inside the housing 110 and an upper surface 12 parallel to the lower surface 11, and the heat radiation fins 20 are provided on the upper surface (predetermined surface) 12.

[0013] The heat radiation fins 20 are plate-shaped members erected on the upper surface 12 of the base portion 10 in a first direction (Y direction) orthogonal to the upper surface 12, and a plurality of them are arranged in parallel in a second direction (X direction) orthogonal to the first direction.

[0014] The heat sink structure 1 of this embodiment is a casting (die-cast product) made of aluminum or an aluminum alloy, and is obtained by integrally casting the base portion 10 and the heat dissipation fins 20 using a mold. For example, the heat sink structure 1 is manufactured by arranging the upper mold and the lower mold that are aligned in the vertical direction, and injecting the molten aluminum alloy into the space formed between the upper mold and the lower mold. In this case, since the cast heat sink structure 1 is extracted from the mold in the Y direction, a draft is provided according to this direction. In the example of FIG. 2, in each heat dissipation fin 20 of the heat sink structure 1, the width W2 on the tip portion 22 side is formed narrower than the width W1 of the base end portion 21 on the base portion 10 side. In other words, in the X-Y cross section of each heat dissipation fin 20, when one of the side surfaces of each heat dissipation fin facing the X direction is defined as the first side surface 23 and the other as the second side surface 24, these first side surface 23 and second side surface 24 are inclined with respect to the upper surface 12 of the base portion so that the interval (width of the heat dissipation fin) narrows as it goes from the base end portion 21 to the tip portion 22. In this way, each heat dissipation fin 20 is formed in a tapered shape so as to be removed from the upper mold.

[0015] Further, as shown in FIG. 2, the heat sink structure 1 makes the drafts of the heat dissipation fins 20 adjacent to each other in the Y direction different.

[0016] In FIG. 2, one of the heat dissipation fins 20 is shown as the heat dissipation fin 20A, and one of the heat dissipation fins 20 adjacent to this heat dissipation fin 20A is shown as the heat dissipation fin 20B.

[0017] In the example of FIG. 2, the inclination θL of the first side surface 23 of the heat dissipation fin 20A with respect to the upper surface 12 of the base portion is 88°, that is, the inclination of the first side surface 23 with respect to the Y axis is 2°. Also, the heat The inclination θR of the second side surface 24 of the fin 20A with respect to the upper surface 12 of the base portion is 86°, that is, the inclination of the second side surface 24 with respect to the Y axis is 4°.

[0018] On one hand, the inclination θL of the first side surface 23 of the heat dissipation fin 20B with respect to the upper surface 12 of the base portion is 86°, that is, the inclination of the first side surface 23 with respect to the Y-axis is 4°. Also, the inclination θR of the second side surface 24 of the heat dissipation fin 20B with respect to the upper surface 12 of the base portion is 88°, that is, the inclination of the second side surface 24 with respect to the Y-axis is 2°.

[0019] Thus, the inclination θL of the first side surface 23 and the inclination θR of the second side surface 24 of the heat dissipation fin 20A are reversed from the inclination θL of the first side surface 23 and the inclination θR of the second side surface 24 of the heat dissipation fin 20B. That is, the cross-sectional shape of the heat dissipation fin 20A and the cross-sectional shape of the heat dissipation fin 20B are formed symmetrically (left-right symmetric) with respect to the Y-axis.

[0020] Also, for the heat dissipation fin 20C adjacent to the heat dissipation fin 20B, the inclination θL of the first side surface 23 with respect to the upper surface 12 of the base portion is 88°, and the inclination θR of the second side surface 24 with respect to the upper surface 12 of the base portion is 86°. Therefore, the inclination θL of the first side surface 23 and the inclination θR of the second side surface 24 of the heat dissipation fin 20B are reversed from the inclination θL of the first side surface 23 and the inclination θR of the second side surface 24 of the heat dissipation fin 20C. In FIG. 2, three heat dissipation fins 20A to 20C arranged at the same height are shown, but four or more can be arranged side by side. Similarly, the inclination θL of the first side surface 23 and the inclination θR of the second side surface 24 are reversed between adjacent heat dissipation fins 20, and cross-sectional shapes similar to those of the heat dissipation fin 20A and cross-sectional shapes similar to those of the heat dissipation fin 20B can be provided alternately. Thus, the heat sink structure 1 of the present embodiment suppresses the resonance between adjacent heat dissipation fins 20 by changing the extraction gradient of adjacent heat dissipation fins 20 and making the cross-sectional shapes different from each other.

[0021] Also, for the heat dissipation fin 20A, the radius of curvature RL of the connection portion between the first side surface 23 and the upper surface 12 of the base portion 10 is 1 mm, and the radius of curvature RR of the connection portion between the second side surface 24 and the upper surface 12 of the base portion 10 is 2 mm. On the other hand, for the heat dissipation fin 20B, the radius of curvature RL of the connection portion between the first side surface 23 and the upper surface 12 of the base portion 10 is 2 mm, and the radius of curvature RR of the connection portion between the second side surface 24 and the upper surface 12 of the base portion 10 is 1 mm.

[0022] In this way, the radii of curvature RL and RR of the connection portions at the base ends of the heat dissipation fins 20A are reversed from the radii of curvature RL and RR of the connection portions at the base ends of the heat dissipation fins 20B.

[0023] Further, for the heat dissipation fin 20C adjacent to the heat dissipation fin 20B, the radius of curvature RL of the connection portion between the first side surface 23 and the upper surface 12 of the base portion 10 is 1 mm, and the radius of curvature RR of the connection portion between the second side surface 24 and the upper surface 12 of the base portion 10 is 2 mm. For this reason, the radii of curvature RL and RR of the connection portions in the heat dissipation fin 20B are reversed from the radii of curvature RL and RR of the connection portions at the base ends of the heat dissipation fin 20C. In FIG. 2, three heat dissipation fins 20A to 20C arranged at the same height are shown, but four or more may be arranged side by side, and the radii of curvature RL and RR at the connection portions of the first side surface 23 are similarly reversed between adjacent heat dissipation fins 20, and cross-sectional shapes similar to those of the heat dissipation fin 20A and cross-sectional shapes similar to those of the heat dissipation fin 20B may be provided alternately. Note that the above-described radii of curvature and curvatures are examples and are not limited thereto.

[0024] In this way, the heat sink structure 1 of the present embodiment suppresses resonance between adjacent heat dissipation fins 20 by changing the radii of curvature of the connection portions in the adjacent heat dissipation fins 20, that is, by changing the curvature of the connection portions and making the cross-sectional shapes different from each other.

[0025] The heat sink structure 1 of the present embodiment further includes heat dissipation fins 20M and 20N having different heights from the heat dissipation fins 20A to 20C. The heat dissipation fins 20M and 20N have the same height, and the heat dissipation fins 20M and 20N adjacent at this same height have the same draft and connection portion curvatures as those of the above-described heat dissipation fins 20A to 20C. Note that the heat dissipation fin 20C and the heat dissipation fin 20M have different heights, and since their cross-sectional shapes are different regardless of the draft, the slopes and the radii of curvature of the connection portions may be the same or different.

[0026] Further, as shown in FIG. 3, in the heat sink structure 1 of the present embodiment, a pressure receiving portion 25 having a wider width than other portions of the tip portion 22 is formed at the tip portion 22 of the heat radiation fins 20. Then, as shown in FIG. 4, after casting, the heat sink structure 1 is extracted from the upper mold 41 by pressing the pressure receiving portion 25 with the extrusion pin 42. Here, if the pressure receiving portions 25 are formed in the adjacent heat radiation fins 20 in the same manner, resonance may occur. Therefore, in the adjacent heat radiation fins 20, the positions where the pressure receiving portions 25 are formed are made different in the depth direction (Z direction). Thereby, the cross-sectional shapes of the adjacent heat radiation fins 20 are made different from each other, and resonance between the adjacent heat radiation fins 20 is suppressed.

[0027] FIG. 5 is a diagram showing the configuration of the audio amplifier 100 according to the present embodiment. In the audio amplifier 100, circuit boards 52 and 53 are provided on the bottom plate 51. The circuit board 52 includes electronic components 521 that are heat sources, such as a power IC and a regulator. The circuit board 53 is provided with a circuit 532 that performs signal processing such as transmission, conversion, amplification, and output of an acoustic signal input from another device.

[0028] Further, on the bottom plate 51, a circuit 30 that is a heat source, such as a power transformer, an electrolytic capacitor, and a switching element, is provided. Note that the circuit 30 and the electronic component 521 are also vibration sources that generate minute vibrations during use.

[0029] An upper cover body 60 is attached to the bottom plate 51 with a fastening member such as a screw. The upper cover body 60 has a side plate portion 61 that defines a side surface of the housing 110, and a top plate portion 62 that is connected to upper ends of the left and right side plate portions 61 and defines an upper surface of the housing 110. Note that the heat sink structure 1 of the present embodiment is formed integrally with the upper cover body 60, and the base portion 10 constitutes a part of the top plate portion 62.

[0030] In addition to this, the housing 110 has a box shape having a front panel (not shown) that defines the front surface and a rear panel (not shown) that defines the rear surface. As described above, the audio amplifier 100 of the present embodiment houses a circuit 532 that performs signal processing, a circuit 30 that serves as a heat source and a vibration source, electronic components 521, etc. in the space within the housing 110. The electronic component 521 is provided in contact with the inner wall surface of the top plate portion 62, that is, the lower surface 11 of the heat sink structure 1, and releases heat to the outside through the heat sink structure 1.

[0031] <Function and Effect> As described above, in the X-Y cross section of the plurality of heat radiation fins 20 arranged side by side, the heat sink structure 1 of the present embodiment makes the inclination of the side surfaces 23 and 24 with respect to the base portion 10 different between adjacent heat radiation fins in the second direction (X direction).

[0032] Thereby, the heat sink structure 1 of the present embodiment makes the cross-sectional shapes of adjacent heat radiation fins different, changes the resonance points, and suppresses the resonance between adjacent heat radiation fins.

[0033] Further, in the X-Y cross section of the heat radiation fin 20, the heat sink structure 1 of the present embodiment makes the curvature of the connection portion between the side surfaces 23 and 24 of the heat radiation fin 20 and the base portion 10 different between adjacent heat radiation fins in the second direction. Thereby, the heat sink structure 1 of the present embodiment makes the cross-sectional shapes of adjacent heat radiation fins different, changes the resonance points, and suppresses the resonance between adjacent heat radiation fins.

[0034] Further, in the X-Y cross section of the heat radiation fin 20, one of the side surfaces of each heat radiation fin 20 facing the second direction is defined as the first side surface 23, and the other is defined as the second side surface 24. The inclination of the first side surface 23 and the inclination of the second side surface 24 are reversed between adjacent heat radiation fins in the second direction. Thereby, the heat sink structure 1 of the present embodiment makes the cross-sectional shapes of adjacent heat radiation fins different, changes the resonance points, and suppresses the resonance between adjacent heat radiation fins.

[0035] Furthermore, in the heat sink structure 1 of the present embodiment, the base portion 10 forms a part of the housing 110 in the audio amplifier (acoustic device) 100. As a result, resonance of the heat sink structure 1 due to minute vibrations generated by the vibration source of the audio amplifier 100 is suppressed, and the influence on the signal circuit due to resonance of the heat sink structure 1 is suppressed, so that deterioration of the sound quality of the audio amplifier 100 can be suppressed.

[0036] <Others> The acoustic device is not limited to the audio amplifier 100, and any device equipped with a circuit that performs acoustic signal processing, such as an audio tuner, a video recording device (recorder), and a playback device (player), may be used.

Explanation of Reference Numerals

[0037] 1 Heat sink structure 10 Base portion 20, 20A to 20C, 20M, 20N Heat dissipation fins 21 Base end portion 22 Tip end portion 23 First side surface 24 Second side surface 25 Pressure receiving portion 30 Circuit 41 Upper mold 42 Extrusion pin 51 Bottom plate 52, 53 Circuit board 60 Upper cover body 100 Audio amplifier (acoustic device) 110 Housing

Claims

1. A heat sink structure used in an audio device, a base portion, a plate-shaped heat dissipation fin erected on a predetermined surface of the base portion in a first direction orthogonal to the predetermined surface, and a plurality of the heat dissipation fins arranged in parallel in a second direction orthogonal to the first direction, comprising: In a cross section parallel to the first direction and the second direction of the heat dissipation fin, the angles of the opposing planar side surfaces of the heat dissipation fins adjacent to each other in the second direction with respect to the base portion are made different so as to suppress resonance due to vibration of the audio device, A heat sink structure in which the curvature of the connection portion between the side surface of the heat dissipation fin and the base portion is made different between the heat dissipation fins adjacent to each other in the second direction.

2. A heat sink structure used in an audio device, a base portion, a plate-shaped heat dissipation fin erected on a predetermined surface of the base portion in a first direction orthogonal to the predetermined surface, and a plurality of the heat dissipation fins arranged in parallel in a second direction orthogonal to the first direction, comprising: In a cross section parallel to the first direction and the second direction of the heat dissipation fin, the angles of the opposing planar side surfaces of the heat dissipation fins adjacent to each other in the second direction with respect to the base portion are made different so as to suppress resonance due to vibration of the audio device, One of the side surfaces of each heat dissipation fin facing the second direction is defined as a first side surface, and the other is defined as a second side surface, and the inclination of the first side surface and the inclination of the second side surface are inverted between the heat dissipation fins adjacent to each other in the second direction. A heat sink structure.

3. The heat sink structure of the audio device according to claim 1 or 2, wherein the base portion constitutes a part of a housing in the audio device.

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