JPH06314888A - Chassis device - Google Patents

Abstract

PURPOSE:To absorb vibrations from a vibration generation source in equipment without transmitting the vibrations to a vibration-sensitive and easily damaged part, and what is more, to enhance vibration resistance effect against vibrations from the outside. CONSTITUTION:Dram parts 40 and 50, are made on a base 31 at a vibration area by drawing work. The drawn part 40 is so designed that the vibrations from a dram surface 41 furnished with a transformer, which is a vibrator, to travel to drawn surfaces 45 and 46 by way of drawn surfaces 43 and 44. As a result, a leg main body on the rear side of the drawn surfaces 45 and 46 and a rubber cushion damp the vibration effectively so that it is difficult to transmit the vibrations to a circuit board. It is also possible to enhance damping effect since the vibrations from a floor surface is damped by the leg main body and the rubber cushion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, in precision equipment such as audio / video equipment or information recording / reproducing equipment, absorbs vibration from a vibration source in the equipment without transmitting it to a portion where the vibration is disliked. The present invention also relates to a chassis device having a high vibration damping effect against external vibration.

[0002]

2. Description of the Related Art For example, as a main vibration source of an audio amplifier, there are a power transformer, an electrolytic capacitor, a power transistor, and the like.
There are sound pressure from the speaker and vibration from other rotating devices. These are transmitted through the chassis and finally vibrate the electronic components, wiring materials, etc. on the circuit board. As a result, the contact resistance, the induced voltage, and the like change, which causes noise and distortion in the audio amplifier and deteriorates the sound quality. Therefore, the structure of each part must be designed so as to be less susceptible to the influence of vibration or to be instantly attenuated even if it is affected.

For this reason, conventionally, the chassis has been made to have a high rigidity such as a honeycomb shape, a partially thickened plate for reinforcement, or a separate member for reinforcement.

Further, in Japanese Patent Laid-Open No. 4-229480, ribs are provided on the chassis to increase the rigidity and to suppress the transmission of vibrations in order to suppress the resonance that occurs during focusing of the optical disk drive. A slit is shown.

Further, Japanese Utility Model Laid-Open No. 3-10579 discloses that
A vibration-damping structure is disclosed in which the vibration generated inside the device body is efficiently transmitted to a leg portion having a vibration damping function via an exterior leg portion.

[0006]

However, in the above-mentioned conventional honeycomb shape and ribs having high rigidity, the amplitude is reduced only in that portion,
Vibration cannot be damped fundamentally. In addition, if the vibration is blocked by the slit, there is a drawback that the strength of the entire chassis is reduced.

Further, the above-mentioned leg damping the vibration is not sufficiently effective because the generated vibration is not transmitted to the parts other than the leg.

The present invention has been made in consideration of such a situation, and absorbs vibrations from a vibration source in a device without transmitting the vibrations to a portion in which the vibrations are disliked, and against vibrations from the outside. As a result, it is an object of the present invention to provide a chassis device capable of enhancing the vibration damping effect and having high strength.

[0009]

In order to achieve the above-mentioned object, the chassis device of the present invention has a harmful vibration generating component and a vibration-proof component attached to one chassis and is arranged via at least one leg. In the chassis device described above, at least one vibration region surrounded by an annular rib is provided in the chassis, the harmful vibration generating component and at least one leg are mounted in the same vibration region, and the vibration isolation target component is mounted. Is attached outside the vibration area.

[0010]

In the chassis device of the present invention, the vibration generated by the harmful vibration generating component is transmitted to the leg through the same vibration region and is damped in the leg. That is, the vibrations from the vibration source inside and outside the device are confined within the vibration region, and the vibration damping effect can be increased even with respect to the vibration from the outside propagating through the leg.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show an embodiment of a chassis when the chassis device of the present invention is mounted on, for example, an audio amplifier. As shown in these drawings, the chassis 30 has a base 31 and side walls 32 and 33 for mounting a circuit board on which various electronic components are mounted on a portion indicated by reference numeral 30a (a region surrounded by a broken line) in FIG. It is manufactured by pressing a sheet metal into a U-shaped cross section.

On the side walls 32, 33 of the base 31 respectively, throttle portions 40, 50 which are vibration regions are provided. Diaphragm surfaces 41 and 42 are provided on the inner side of the diaphragm portion 40, and a transformer (not shown) that is a vibration source is attached to the diaphragm surface 41. The diaphragm state of each diaphragm surface 41, 42 has a cross section shown in FIG. That is, the X-shaped diaphragm surface 42 is at the same height as the base 31, but this portion is for reinforcing the diaphragm surface 41, and the shape and height (depth) may be appropriately determined. On both sides of the diaphragm surface 41, curved diaphragm surfaces 43 and 44 are provided. At the ends of the respective diaphragm surfaces 43, 44, there are screw surfaces 45, 4 having screw insertion holes 45a, 46a.
6 is provided.

Here, the diaphragm surfaces 41, 43, 44, 45,
The drawing ribs 41a, 43a, 44a, 45b, 46b are provided between the base plate 46 and the base 31 by drawing, and these drawing ribs 41a, 43a, 44a, 45 are provided.
An annular rib is formed by b and 46b. Also,
These diaphragm ribs 41a, 43a, 44a, 45b, 46
The thickness of b is inevitably thinner than the plate thickness of the base 31, which is the original thickness, by drawing, and this portion is stretched and plastically deformed. It is known that rigidity is increased by such plastic deformation, and the rigidity is further enhanced in addition to the effect of geometrical reinforcement. Therefore, the vibration of the transformer generated in the narrowed portion 40 surrounded by the annular rib is suppressed in amplitude at the annular rib portion. Phenomenonally, it is considered that the vibration wave is reflected or attenuated at this portion, and the effect that the vibration is hard to be transmitted over the rib is produced.

As shown in FIG. 4, the respective diaphragm surfaces 41, 43, 44, 45 and 46 are smoothly connected to each other without a steep step so that vibration can be easily transmitted. To the diaphragm surfaces 43, 44, 41, the projection amount gradually increases. As a result, no parallel surface is formed between the floor surface and each of the diaphragm surfaces 43, 44, 45, 46, so that a standing wave is unlikely to stand between them. Further, here, the back side of each of the diaphragm surfaces 45 and 46 serves as a leg mounting portion described later.

The throttle unit 50 is similar to the throttle unit 40 except that it does not have a transformer mounting portion. That is, a diaphragm surface 51 surrounded by annular ribs formed by the diaphragm ribs 51a, 52b, 53b and extending in the front-rear direction, and diaphragm surfaces 52, 53 having screw insertion holes 52a, 53a are provided. Here, the rear surfaces of the diaphragm surfaces 52 and 53 serve as leg mounting portions described later.

The diaphragm states of the diaphragm surfaces 51, 52 and 53 are, as shown in FIG. 5, from the diaphragm surfaces 52 and 53 at both ends to the diaphragm surface 5.
The shape is such that the amount of protrusion gradually increases toward the central portion of No. 1 so that a parallel surface is not formed with the floor surface.

Further, the reason why the diaphragm 50 is curved is that
A parallel plane is not formed between the narrowed portion 40 and the base 31 either on the base 31 or in the space, so that the standing wave is not generated between them and the rigidity of the base 31 is increased.
This is because it is difficult for the vibration of itself to occur.

6 to 9 show the above-mentioned throttle portions 40 and 50.
This shows a leg attached to the leg attachment portion on the back side of the diaphragm surfaces 45, 46, 52, 53, and has a cylindrical shape. Here, the leg main body 60 is made of a highly damped resin material having a large internal loss with respect to vibration, which is injection-molded with a composite material of nylon powder and iron, for example. The ring-shaped fitting groove 6 is formed on the upper and lower surfaces of the leg body 60.
1, 62 are engraved, and these fitting grooves 61, 62 are engraved.
The ring-shaped anti-vibration rubbers 63 and 64 are fixed to each other with an adhesive or the like.

At the center of the leg body 60, a warhead-shaped screw insertion recess 65 having a gradually increasing diameter is formed, and a screw insertion hole 67 into which a screw 66 is inserted is formed at the center. . Here, the reason why the screw insertion concave portion 65 has a warhead shape is that a parallel plane is not formed inside and a standing wave is less likely to occur in the space.

Next, the vibration absorbing function of the chassis device having the above-described structure will be described. First, for example, a commercial power source of 50 Hz is supplied to the transformer mounted on the diaphragm surface 41 of the diaphragm section 40. For this reason,
The transformer itself vibrates at a frequency of 50Hz or its high frequency component. This vibration is caused by the diaphragm surfaces 43, 4 as described above.
4 is transmitted to the diaphragm surfaces 45 and 46. At this time, the vibration in the throttle portion 40 is not transmitted to the outside by the annular rib surrounding the throttle portion 40 described above. Therefore, all the vibrations in the diaphragm portion 40 reach the diaphragm surfaces 45 and 46, and are transmitted to the leg body 60 attached to the rear surface thereof as shown by an arrow A in FIG. Here, since the leg body 60 is made of a highly damped resin material as described above, the vibration transmitted to the inside of the leg body 60 is attenuated by being converted into heat energy inside the leg body 60. Further, the vibration component that flows backward from the inside of the leg body 60 and is shown by the arrow B in the figure is attenuated by the vibration isolating rubber 63 and is not transmitted to the board mounting portion 30a.

Further, as described above, since the screw insertion concave portion 65 of the leg main body 60 is formed into a warhead shape, a standing wave is not generated in the internal space of the leg main body 60 and vibration is not likely to be enhanced.

On the other hand, the vibration transmitted from the floor is shown in FIG.
As indicated by the arrow C in FIG. 1, the vibration is transmitted to the inside of the leg body 60 via the vibration-proof rubber 64, but is also attenuated by being converted into heat energy. Further, the vibration component shown by the arrow D in the figure from the inside of the leg body 60 to the upper side is damped by the vibration isolating rubber 63.

As indicated by arrow E, even if there is vibration flowing into the leg mounting portion, it is transmitted to the other leg through the throttle portions 43, 44, 51 and the like, and is damped there. This is the reason why, in the diaphragm portion 50, both leg mounting portions are connected by the diaphragm surface, even though the vibrating body is not mounted on the diaphragm surface.

Further, since no parallel surface is formed between the floor surface and each of the diaphragm surfaces of the diaphragm portions 40 and 50, no standing wave is generated. Further, as described above, since the narrowed portions are curved and face each other, there is no parallel portion on the base 31, and no standing wave is generated inside the base 31. At the same time, since the rigidity of the base 31 itself is increased, overall vibration is also suppressed.

FIG. 12 shows the results of measuring the transfer characteristics of low-frequency (.about.250 Hz) vibrations from the vibration source attached to the diaphragm surface 41. It is assumed that the diaphragm portion of FIG. 13 is not provided. By contrast, the damping property becomes clear. That is, the characteristic indicated by the solid line in the figure shows the transmission characteristic to the leg mounting portion, and when focusing on the fundamental frequency of 50Hz of the above-mentioned transformer, the transmission level is about -5 dB. Further, the characteristic indicated by the dotted line in the figure shows the transmission characteristic to the circuit board mounting portion 30a, and is the same as the above.
Focusing on HZ, the transfer level is about -11 dB.

On the other hand, in the case of the one shown in FIG. 13, it is about −13 dB and about −5 dB, respectively, similarly to the above.
This means that in the case of the present embodiment having the throttle portion, the transmission of vibration to the leg is good, and in the case of not having the throttle portion, the transmission of vibration to the circuit board is good. In other words, most of the vibration will be transmitted to the leg and will disappear there.

As described above, in this embodiment, the base 31 is provided with the diaphragm portions 40 and 50 which are vibration regions by the drawing process, and the diaphragm portion 40 vibrates from the diaphragm surface 41 to which the transformer which is the vibration member is attached. The diaphragm surfaces 43, 44
To facilitate transmission to the diaphragm surfaces 45 and 46. Therefore, the leg body 60 and the anti-vibration rubbers 63 and 64 on the rear side of the diaphragm surfaces 45 and 46 efficiently dampen the vibrations and are difficult to transmit to the circuit board.

Further, the vibration transmitted from the floor surface is reduced by the throttle unit 40.
And the diaphragm surfaces 45, 46 and the diaphragm surfaces 52, 5 of the diaphragm unit 50.
Since the vibration is damped by any one of the leg bodies 60 and the vibration-proof rubbers 63 and 64 attached to the back side of the No. 3, the vibration-proof effect is maintained.

In the above embodiment, the diaphragm surfaces 41, 43, 44, 45, 46, 5 serving as vibration transmission paths.
Although the cross-sectional shape of the annular ribs defining 1, 52, 53 is a single descending step, it may be an ascending step, as shown in FIG. As shown in c), it may have a concave or convex groove shape, or a combination thereof.

In the above embodiment, the case where the chassis device of the present invention is mounted on, for example, an audio amplifier to absorb the vibration of the transformer has been described, but the present invention is not limited to this example, and the present invention is applied to, for example, a video device. Alternatively, it may be incorporated in a precision device such as an information recording / reproducing device to absorb vibration of a motor or the like.

In the above embodiment, the chassis in which the annular rib is formed by drawing the sheet metal is shown, but it can be applied to the chassis formed of resin. However,
In the case of resin, the characteristics of the material are uniform even in the rib portion, so that the reflection or attenuation of the vibration wave is unlikely to occur. Therefore, by mixing another material only in the rib portion or changing the thickness, the same effect can be obtained by supplementing this.

[0032]

As described above, according to the chassis device of the present invention, the chassis is provided with at least one vibrating region surrounded by the annular rib, and the harmful vibration generating component and at least one leg are vibrated in the same vibration. In addition to being installed inside the area, the parts to be isolated from vibration were installed outside the vibration area, so the vibration from the vibration source inside the equipment can be confined within the vibration area without reducing the strength of the chassis, and the parts that do not like vibration can be suppressed. It can be absorbed without being transmitted, and vibrations from the outside can be further enhanced by the legs provided in the vibration region.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment in which a chassis device of the present invention is applied to a chassis mounted on, for example, an audio amplifier.

2 is a plan view showing the base of FIG. 1. FIG.

3 is a cross-sectional view taken along the line III-III in FIG.

FIG. 4 is a left side view showing a state in which legs are attached to the chassis of FIG.

5 is a right side view showing a state in which legs are attached to the chassis of FIG.

FIG. 6 is a diagram showing a leg attached to a leg attaching portion on the back side of the aperture surface of the aperture unit of FIG. 1;

7 is a cross-sectional view showing the leg of FIG.

8 is a plan view showing the leg of FIG. 7. FIG.

9 is a bottom view showing the leg of FIG. 7. FIG.

FIG. 10 is a diagram for explaining a vibration damping operation by the legs of FIG. 7.

FIG. 11 is a diagram for explaining a vibration damping operation by the legs of FIG.

FIG. 12 is a diagram showing a vibration transfer characteristic in an example using the chassis of FIG. 1;

FIG. 13 is a diagram showing a transmission characteristic of vibration when the chassis without the throttle portion of FIG. 1 is used.

14 is a diagram showing another shape when the cross-sectional shape of the diaphragm surface in FIG. 7 is changed.

[Explanation of symbols]

30 chassis 30a circuit board mounting portion 31 base 40, 50 throttle portion 41, 42, 43, 44, 45, 46, 51, 52, 5
3 Drawing surfaces 41a, 42a, 43a, 44a, 45b, 46b, 5
1a, 52b, 53b Drawing rib 60 Leg body 63, 64 Anti-vibration rubber 65 Screw insertion recess

Claims (1)

[Claims] 1. A chassis device in which a harmful vibration-generating component and a vibration-proof component are attached to one chassis and arranged via at least one leg, wherein at least one chassis surrounded by annular ribs is provided on the chassis. A chassis device, wherein a vibration region is provided, the harmful vibration generating component and at least one leg are mounted in the same vibration region, and the vibration isolation target component is mounted outside the vibration region.