Board structure of audio equipment

Abstract

A technique for effectively suppressing vibration of a plate for an audio device is provided. The plate structure of the audio device comprises: a flat plate portion constituting at least a portion of the plate for the audio device; a first drawn portion being a portion of the flat plate portion, being recessed in the wall thickness direction relative to a given plane orthogonal to the wall thickness direction of the flat plate portion, and having a rectangular shape in a plan view of the given plane; and a second drawn portion being a portion of the flat plate portion, being recessed in the wall thickness direction relative to the given plane, and having a rectangular shape in a plan view of the given plane, wherein the first drawn portion and the second drawn portion are configured such that a given gap is provided between the first drawn portion and the second drawn portion, and wherein the first drawn portion and the second drawn portion are configured such that when the flat plate portion vibrates and a standing wave is formed in the flat plate portion, the gap is formed at the antinode of the standing wave.

Description

Technical Field

[0001] The invention relates to a plate structure for an audio device. Background Art

[0002] In audio equipment that processes sound signals, such as audio amplifiers, audio tuners, video recorders (recorders), and playback devices (players), if vibrations are transmitted to the circuits that process sound signals, the electronic components and wiring materials that constitute the circuits will vibrate. As a result, changes in contact resistance, induced voltage, etc. in these elements may add noise to the sound signal, distort the sound signal, and become a major cause of sound quality degradation.

[0003] Patent document 1 describes a device in which at least one vibration region surrounded by an annular rib is provided on a base, a harmful vibration generating component and at least one leg are installed in the same vibration region, and a vibration isolation target component is installed outside the aforementioned vibration region, thereby making it possible to suppress the influence of vibration on the vibration isolation target component.

[0004] Prior Art Literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 6-314888

[0007] As the main causes of vibration in audio equipment, for example, the power transformer, electrolytic capacitor, power transistor, etc. that the equipment itself has can be cited. In addition, it is also considered that the pressure (sound pressure) of the sound output from the speaker and the vibration from the rotating mechanism, etc. are the main causes. Although these vibrations are designed to be small vibrations, even if they are small vibrations, if the housing of the device resonates, for example, the vibration will become larger, and sometimes it will affect the circuit that processes the sound signal. Therefore, it is desirable to set the device structure to be able to suppress the resonance of the housing.

[0008] As a method of suppressing the resonance of the housing, it is conceivable to reduce the resonance between the components by reducing the number of components. However, there is a problem that the components that can be reduced are not necessarily provided, and the situations in which they can be applied are limited.

[0009] In addition, as a method of suppressing the resonance of the shell, it is possible to increase the rigidity by thickening the shell wall. However, if the shell wall is thickened, the weight of the device increases, so there is a problem that it is difficult to apply to devices that require lightweight, such as vehicle-mounted devices. Furthermore, if the shell wall is thickened, it will lead to an increase in material costs and an increase in processing costs, so it is not a method that can be easily selected.

[0010] Therefore, it is also possible to consider providing a drawn portion on the flat plate portion of the shell to partially strengthen the shell without increasing weight or material costs. However, there is a problem that if only one part is strengthened, the vibration of other parts becomes greater and cannot be fundamentally solved. Summary of the invention

[0011] An object of the present invention is to provide a technology for effectively suppressing vibration of a plate material used in an audio device.

[0012] In order to solve the above problems, the plate structure of the audio equipment according to the present invention comprises:

[0013] a flat plate portion constituting at least a portion of a plate for the audio device;

[0014] A first drawn portion, which is a portion of the flat plate portion, is recessed in the wall thickness direction relative to a given plane orthogonal to the wall thickness direction of the flat plate portion, and has a rectangular shape when viewed from above the given plane; and

[0015] The second drawn portion is a portion of the flat plate portion, is recessed in the wall thickness direction relative to the given plane, and has a rectangular shape when the given plane is viewed from above.

[0016] The first drawn portion and the second drawn portion are arranged so that a given gap is provided between the first drawn portion and the second drawn portion.

[0017] The first drawn portion and the second drawn portion are arranged so that, when the flat plate portion vibrates to form a standing wave in the flat plate portion, the gap is formed at the antinode of the standing wave.

[0018] According to the present invention, it is possible to provide a technique for effectively suppressing vibration of a plate material used in audio equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a top view of a bottom plate to which the plate structure according to the embodiment is applied.

[0020] Figure 2 yes Figure 1 Cross-sectional view at line AA.

[0021] Figure 3 This is a schematic cross-sectional view of an audio amplifier having a plate structure according to an embodiment.

[0022] Figure 4 This is a diagram showing the vibration state of the base plate detected by a vibration pickup, with the areas divided according to the magnitude of the vibration.

[0023] Description of Reference Numerals

[0024] 1: Bottom plate;

[0025] 10: Flat plate;

[0026] 11: First drawing section;

[0027] 12: Second drawing section;

[0028] 13: Gap;

[0029] 14: Establishment Department;

[0030] 15: substrate supporting portion;

[0031] 20: Circuit board;

[0032] 20X: center;

[0033] 40: upper covering body;

[0034] 51-54: Area;

[0035] 100: Audio amplifier. DETAILED DESCRIPTION

[0036] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 1 is a top view of a bottom plate 1 to which the plate structure according to the present embodiment is applied. Figure 2 yes Figure 1 The cross-sectional view at line AA of Figure 3 FIG. 1 is a schematic cross-sectional view of an audio amplifier 100 having a plate structure according to the present embodiment. Figure 1 to Figure 3 In the figure, the X axis represents the width direction, the Y axis represents the height direction, and the Z axis represents the front-rear direction. These directions are shown for convenience of explanation, and the plate structure of this embodiment is not limited to being arranged in the directions shown in the figure.

[0037] The bottom plate 1 is a substantially flat plate to which the plate structure according to the present embodiment is applied. The bottom plate 1 constitutes a part (bottom) of the housing 110 of the audio amplifier 100 .

[0038] The bottom plate 1 has: a flat plate portion 10, which constitutes at least a portion of the bottom plate 1 and is parallel to the XZ plane (horizontal plane); a first drawn portion 11, which is provided by drawing a portion of the flat plate portion 10; and a second drawn portion, which is formed by the same drawing process. In addition, the bottom plate 1 of the present embodiment has: a vertical portion 14, which bends the end of the flat plate portion 10 in the left-right direction (X direction) upward; and a substrate support portion 15, which is formed by deep drawing a portion of the flat plate portion 10 upward into a truncated cone shape. In addition, Figure 1 to Figure 4The bottom plate 1 shown is an example, and is not limited to this structure. Any structure may be used as long as it includes a flat plate portion 10 and a first drawn portion 11 and a second drawn portion 12 provided on a part of the flat plate portion 10 .

[0039] like Figure 3 As shown, a circuit board 20 is placed on the upper surface 151 of the board support portion 15 of the base plate 1, and the circuit board 20 is fastened to the board support portion 15 by a fastening member such as a screw. The circuit board 20 is provided with a circuit 21 that performs signal processing such as transmission, conversion, amplification, and output of a sound signal input from another device. In addition, the circuit 21 is one form of a circuit that processes a sound signal.

[0040] Furthermore, a circuit 30 serving as a vibration source, such as a power transformer, an electrolytic capacitor, and a switching element, is provided on the base plate 1 .

[0041] The upper cover 40 is attached to the upright portion 14 of the base plate 1 by means of fastening members such as screws. The upper cover 40 includes: a side plate portion 41 that divides the side surface of the housing 110; and a top plate portion 42 that is connected to the upper ends of the left and right side plates 41 and divides the upper surface of the housing 110. In addition, the housing 110 is a rectangular parallelepiped having a front panel (not shown) that divides the front surface and a rear panel (not shown) that divides the rear surface. In this way, the audio amplifier 100 of this embodiment accommodates the circuit 21 for signal processing, the circuit 30 that serves as a vibration source, and the like in the space inside the housing 110.

[0042] like Figure 2 As shown, the first drawn portion 11 and the second drawn portion 12 are depressions (recesses) drawn in the wall thickness direction relative to the lower surface (given plane) 10A orthogonal to the wall thickness direction (Y direction) of the flat plate portion 10, as shown in FIG. Figure 1 As shown in FIG. 1 , the outer shape of the lower surface 10A when viewed from above is formed into a rectangular shape. In addition, the first drawn portion 11 and the second drawn portion 12 are arranged side by side in a given direction (X direction) with a given gap 13 therebetween.

[0043] The sides (outer edges) 111, 113 of the first drawn portion 11 and the sides (outer edges) 121, 123 of the second drawn portion 12 that are opposite in the Z direction are formed parallel to the sides (outer edges) 101, 103 of the flat plate portion 10, respectively. In addition, the sides (outer edges) 112, 114 of the first drawn portion 11 and the sides (outer edges) 122, 124 of the second drawn portion 12 that are opposite in the X direction are formed parallel to the sides (outer edges) 102, 104 of the flat plate portion 10, respectively. That is, the side 112 of the first drawn portion 11 on the side of the gap 13 and the side 124 of the second drawn portion 12 on the side of the gap 13 are formed parallel to each other.

[0044] Furthermore, as described above, the first drawn portion 11 and the second drawn portion 12 are arranged in the X direction with the gap 13 therebetween, and the gap 13 is arranged at a position deviated from the straight line (center line) 10X passing through the center of the flat plate portion 10 in the Z direction in the arrangement direction (X direction). Furthermore, in the arrangement direction (X direction), the width W13 of the gap 13 is formed to be narrower than either the width W11 of the first drawn portion 11 or the width W12 of the second drawn portion 12. Furthermore, the width W11 of the first drawn portion 11 is formed to be different from the width W12 of the second drawn portion 12. That is, as follows:

[0045] W13<W11… (Formula 1)

[0046] W13<W12… (Formula 2)

[0047] W11≠W12… (Equation 3).

[0048] <Effects>

[0049] As described above, in the base plate 1 of the present embodiment, when the audio amplifier 100 is used, the flat plate portion 10 vibrates due to minute vibrations generated from a vibration source such as the circuit 30, and the first drawn portion 11 and the second drawn portion 12 are configured so that when a standing wave is formed in the flat plate portion 10, the gap 13 is formed at the antinode of the standing wave.

[0050] Figure 4 This is a diagram showing the vibration state of the base plate 1 detected by a vibration pickup, and the regions 51 to 54 are divided according to the magnitude of the vibration. Figure 4 In the example, region 51 is the region with the largest vibration and is the antinode of the standing wave. From region 51 to region 54, the vibration gradually decreases, and region 54 is the region with the smallest vibration. In addition, the vicinity of the boundary between region 53 and region 54 is the node of the standing wave. Figure 4 As shown, the first drawn portion 11 and the second drawn portion 12 are arranged so that the gap 13 is formed in the region 51. In particular, Figure 4 In the example, the first drawn portion 11 and the second drawn portion 12 are arranged so that the corners are located in the region 51. Furthermore, the first drawn portion 11 and the second drawn portion 12 are arranged so that the sides 113 and 114 of the first drawn portion 11 and the sides 122 and 123 of the second drawn portion 12 are along the boundary between the region 53 and the region 54, that is, the node of the standing wave.

[0051] Thus, in this embodiment, the edge 112 of the first drawn portion 11 and the edge 124 of the second drawn portion 12 are used to enhance the position of the antinode of the standing wave where the vibration becomes larger, thereby suppressing the vibration, and the other edges 111, 113, 114, 121 to 123 are used to suppress the vibration of other parts caused by the enhancement of this part, thereby effectively suppressing the resonance of the bottom plate 1.

[0052] In the present embodiment, the gap 13 is disposed at a position offset from the center 20X of the flat plate portion 10 in the X direction, and the vibration states of the left and right sides are made different with the gap 13 as a boundary, thereby suppressing the resonance of the base plate 1 .

[0053] Furthermore, in the present embodiment, in the X direction, the width W13 of the gap 13 is formed to be narrower than either the width W11 of the first drawn portion 11 or the width W12 of the second drawn portion 12. Thus, the vibration state near the first drawn portion 11 and the vibration state near the second drawn portion 12 are made different, and the resonance of the bottom plate 1 is suppressed.

[0054] <Others>

[0055] In the above-mentioned embodiment, an example of applying the plate structure to the bottom plate of the audio amplifier 100 is shown, but it is not limited to this, and it can also be applied to the side plate and the top plate. In addition, it is not limited to the housing, and it can also be applied to the plate constituting the partition plate, the base, etc. set in the housing. Furthermore, as an audio device to which the plate structure is applied, it is not limited to the audio amplifier 100, as long as it is an audio tuner, a video recording device (recorder), and a playback device (player) that has a circuit for processing sound signals.

Claims

1. A plate structure of an audio device, comprising: a flat plate portion constituting at least a portion of a plate for the audio device; A first drawn portion, which is a portion of the flat plate portion, is recessed in the wall thickness direction relative to a given plane orthogonal to the wall thickness direction of the flat plate portion, and has a rectangular shape when viewed from above the given plane; and The second drawn portion is a portion of the flat plate portion, is recessed in the wall thickness direction relative to the given plane, and has a rectangular shape when the given plane is viewed from above. The first drawn portion and the second drawn portion are arranged so that a given gap is provided between the first drawn portion and the second drawn portion. The first drawn portion and the second drawn portion are arranged so that, when the flat plate portion vibrates to form a standing wave in the flat plate portion, the gap is formed at the antinode of the standing wave.

2. The plate structure of the audio device according to claim 1, wherein: The first drawn portion and the second drawn portion are arranged in a given direction with the gap therebetween. The gap is arranged at a position deviated from a center of the flat plate portion in the given direction.

3. The plate structure of the acoustic device according to claim 1 or 2, wherein: The first drawn portion and the second drawn portion are arranged in a given direction with the gap therebetween. In the given direction, the width of the gap is formed to be narrower than any one of the width of the first drawn portion and the width of the second drawn portion.

Images