JPH061800U - Fan fixing device - Google Patents

Abstract

(57) [Summary] [Objective] To provide a fan fixing device capable of further reducing fan noise. [Structure] The discharge side portion of the fan 1 is fitted and fixed to the suction side portion of the expansion type noise reduction box body 3 made of elastic rubber, and the discharge side portion of the expansion type noise reduction box body 3 is connected to the device housing side. The structure is fixed to the substrate 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fan fixing device capable of reducing fan noise.

[0002]

[Prior art]

 For example, some electronic equipment such as copiers and computers have a heat source and a source of gas to be exhausted, which effectively promotes the internal heat exhaustion function and exhaust function. Therefore, various fans are installed.

Conventionally, such a fan is fixed to the apparatus housing by, for example, the following method. In FIG. 5, the fan 101 is fixedly attached to the device housing substrate 102, and when the fan 101 operates, external air flows into the device 103 from the A direction, and the inflowing air flows in the B direction. Is discharged to. During this time, the power supply 104 and the semiconductor 106 on the printed board 105 are cooled by the flowing air.

For example, as shown in FIG. 6, the fan 101 is directly fixedly attached to the apparatus housing substrate 102 with a long screw 107. Alternatively, as shown in FIGS. 7 and 8, a screw 108 is inserted from the side of the device housing substrate 102, and the flange portion 101 a of the fan 101 is attached to the device housing substrate 102 by the screw 108 and the nut 109. Fixedly attached to. In addition, Japanese Utility Model Laid-Open No. 63-48999 discloses the above fixing method.

In general, in a system in which a fan is directly attached to a device housing substrate, the wind noise of the fan is radiated to the outside as it is, and noise is likely to be generated.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fan fixing device capable of further reducing the noise of such a fan.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention uses an expansion type sound absorbing box body, connects a discharge side part of a fan and a suction side part of the expansion type sound absorbing box body, and discharges the expansion type sound absorbing box body. It proposes a fan fixing device in which the side portion is fixedly connected to the device casing.

In addition, it is effective that the expansion type sound deadening box body is an elastic body having a vibration isolation function.

Further, it is effective to use the fan as an axial flow fan and fix the eddy current prevention member to the leeward side portion of the rotary mounting blade shaft portion.

Further, it is effective to provide a suction guide member for collecting the wind at the suction side portion of the fan.

Further, it is effective to form a concave groove portion on the suction side wall portion of the expansion type sound deadening box body, and to fit a flange portion provided on the discharge side portion of the fan into the concave groove portion.

Further, it is effective that the eddy current prevention member is formed in a conical shape and the bottom surface thereof is a fixed installation surface.

Further, it is effective to form the suction guide member into a cylindrical shape and gradually widen the suction side end portion thereof toward the outside.

[0014]

【Example】

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

FIG. 1 is a sectional view of a fan fixing device according to an embodiment of the present invention.

In this figure, reference numeral 1 is a fan, 2 is a device housing substrate, and 3 is an inflatable muffler box. Of these, the fan 1 is, for example, an axial fan including a rotary blade 5 and a rotary blade mounting shaft portion 6. As shown in FIG. 2, the expandable sound-deadening box body 3 is such that the cross-sectional area of the interior 3B is enlarged relative to the cross-sectional area of the suction port portion 3A.

A feature of the fan fixing device of the present embodiment is that the expansion type sound deadening box body 3 having such a structure is used, and the discharge side portion of the fan 1 and the suction side portion of the expansion type sound deadening box body 3 are mutually connected. In addition, the discharge side portion of the expandable sound-deadening box body 3 is fixedly connected to the apparatus housing substrate 2.

Further, the fixing method will be specifically described. In FIG. 2, the expansion type sound deadening box body 3 is made of an elastic body such as rubber having a vibration damping function, and a wall on which the suction port portion 3A is located. A concave groove portion 7 (FIG. 3) is provided in the portion.

On the other hand, the fan 1 is provided with flange portions 1a and 1b at the suction side portion and the discharge side portion, respectively, and the discharge side flange portion 1b is fitted into the concave groove portion 7 to form a fan. 1 is fixed to the inflatable muffler box 3. A metal nut 8 having a female screw engraved therein is inserted and fixed to the wall portion located at the discharge port portion 3C of the inflatable sound-deadening box body 3. From the side of the device housing substrate 2, a screw 9 is inserted through the hole 2a of the device housing substrate, and the screw 9 is screwed into the nut 8, so that the fan 1 and the expansion type sound-absorbing box body 3 are installed in the device. It is fixed to the housing substrate 2.

In this example, a suction guide member 4 for collecting wind is attached to the suction side portion of the fan 1. The suction guide member 4 has a cylindrical shape having a flange portion 4B at its end, and the opposite end 4A has a curved surface shape that gradually expands outward.

A screw 10 is passed through the hole 4B ₁ of the flange portion 4B of the suction guide member 4, and the screw 10 is further passed through the hole 1a ₁ of the flange portion 1a of the fan 1, and the nut 11 is tightened in this state. As a result, the suction guide member 4 is fixed to the fan 1 as shown in FIG.

In this example, the expansion guide silencer body 3, such as the suction guide member 4 and the fan 1, is fixed to the device housing substrate 2, and the arrangement state with respect to these substrates 2 is , For example, as in FIG. FIG. 1 shows the fixing completion state. And FIG. 3 is the exploded perspective view.

In this way, when the fan 1 attached to the device housing substrate 2 via the expansion type sound deadening box body 3 operates, air enters from the suction side portion of the suction guide member 4 in the direction of arrow A. From the opening 2b of the apparatus housing substrate 2, the material flows in the direction of arrow B and is discharged to the outside of the housing.

As described above, the inflatable sound-deadening box body 3 has a portion 3B in which the cross-sectional area expands from the suction side of wind (air) toward the leeward side, and the discharge side is connected to the suction side again. It is narrowed down to almost the same cross-sectional area. As described above, the expansion-type sound deadening box body 3 is made of, for example, rubber, and the rubber hardness thereof is such that a natural frequency sufficient to block the noise emitted by the fan 1 can be obtained. To be elected.

Here, the sound deadening theory of the expansion type sound deadening box body 3 will be described. Now, in FIG. 1, the cross-sectional area of the suction port portion 3A of the expansion type sound deadening box body 3 is S ₀ , and the cross-sectional area of the expanded portion 3B is Assuming that S is S, the length of the enlarged portion 3B is L, and S / S ₀ = m, the noise attenuation amount is expressed by the following equation. Attenuation = ₁₀ log ₁₀ [1+ {m− (1 / m)} ² × 1/4 × sinKL] [dβ] where K is 2πf / c, f is the frequency of the sound source, and c is It is the speed of sound.

Based on such a theoretical formula, the sound generated from the fan 1 is attenuated, and the fan noise is reduced. In other words, the wind noise of the fan can be turned off.

By the way, when the fan 1 operates, the wind-cutting vibration, the rotational vibration of the fan driving motor, and the like propagate to the device housing substrate 2, and noise is generated from the device housing substrate 2. It will be easier. The inflatable sound-deadening box body 3 is made of elastic rubber as described above. However, if such elastic rubber is used in the inflatable sound-deadening box body, it may cause wind-vibration of a fan or a motor. Rotational vibrations and the like are less likely to propagate to the device housing substrate, and the generation of noise from the device housing substrate can be suppressed. As the expansion type sound deadening box body 3, in addition to rubber, another elastic body capable of obtaining a natural frequency capable of blocking the vibration generated by the fan may be used.

By the way, FIG. 4 shows a general configuration of an axial fan. In this axial fan, a plurality of blades 5 are provided on a rotary shaft 6, and at the time of rotation, a vortex 12 is generated in the exhaust side portion of the rotary shaft, and a vortex sound at this time is generated. Is radiated to generate noise, and the efficiency of the fan is likely to decrease.

As shown in FIGS. 1 and 2, an eddy current prevention member 13 is fixed to the leeward side portion of the rotary blade mounting shaft portion 6 by, for example, an adhesive method. By providing such a swirl preventive member 13 on the shaft portion 6, it is possible to prevent swirl noise, reduce the resistance of the flowing air, and increase the air volume. In particular, when the bottom surface of the eddy current prevention member 13 is a fixed installation surface for the shaft portion 6, it has a conical shape, and the cross-sectional area of the air passage gradually increases toward the leeward side. Can be effectively suppressed.

By the way, the conventional fan fixing method described at the beginning requires long special screws and nuts, but in the case of this example, the flange portion 1b of the fan 1 is attached to the expansion silencer box. Since it is a method of fitting in the concave groove portion 7 (FIG. 2) of the body 3, in other words, the fan can be fixed with one touch, so that tools etc. are not required and the assemblability is significantly improved. Become. It also helps to reduce the number of parts.

As described above, FIG. 4 shows a general configuration of the axial flow fan. At the time of this rotational operation, the air flow on the suction side is parallel to the traveling direction of the air. In addition to the flow 14 that flows, the flow 15 from the side direction is also included. If such a flow 15 exists, the cooling efficiency of the target object to be cooled and the discharge efficiency of the gas to be discharged are poor. To become.

As described above, the suction guide member 4 is fixedly attached to the suction side portion of the fan 1. When the suction guide member 4 is directed to or close to the target object to be cooled, the source of gas to be discharged, or the like, the cooling efficiency and the gas discharging efficiency can be improved. it can. In particular, as shown in Fig. 1, if the suction side end of the cylindrical body is widened to the outside, eddy current can be prevented from being generated due to the edge effect at the end, and cooling efficiency and gas discharge efficiency can be improved. It can be raised further.

The fixing of the fan 1 to the inflatable sound deadening box body 3 and the fixing of the inflatable sound deadening box body 3 to the device housing substrate 2 are not limited to the above-described method, and the fan 1 is not limited thereto. May be fixed to the inflatable sound-deadening box body 3 with a screw or the like, or the inflatable sound-deadening box body 3 may be adhesively fixed to the apparatus housing substrate 2. Further, the fan is not limited to the axial fan, but may have another structure, such as a siroc fan or a conventional fan, as long as the same function can be achieved.

The present invention can be widely applied to a fixing device for a fan for ventilating a house, a warehouse, a vehicle, or the like.

[0035]

[Effect of device]

 According to the configuration described in claim 1, the noise generated from the fan, that is, the wind noise can be further reduced.

According to the configuration of the second aspect, the windbreak vibration of the fan and the rotational vibration of the motor are less likely to propagate to the equipment housing, and noise from the equipment housing is less likely to occur. it can.

According to the configuration of claim 3, whirlpool noise can be prevented, the air resistance can be reduced, and the air volume can be further increased.

According to the configuration described in claim 4, it is possible to improve the cooling efficiency of the cooled object and the discharge efficiency of the gas to be discharged.

According to the configuration described in claim 5, the fan can be fixed with one touch, and the assembling property can be improved.

According to the configuration of claim 6, it is possible to more reliably suppress the generation of the vortex flow.

According to the configuration of claim 7, it is possible to further improve the cooling efficiency of the cooled object and the exhaust efficiency of the gas to be discharged.

[Brief description of drawings]

FIG. 1 is a sectional view of a fan fixing device according to an embodiment of the present invention.

FIG. 2 is an exploded sectional view of a fan fixing device according to an embodiment of the present invention.

FIG. 3 is an exploded perspective view of a fan fixing device according to an embodiment of the present invention.

FIG. 4 is a diagram showing a general configuration of an axial fan.

FIG. 5 is a plan view of an example of a device having a fan.

FIG. 6 is an exploded perspective view of a conventional fan fixing device.

FIG. 7 is an assembly diagram of a conventional fan fixing device.

FIG. 8 is a perspective view of a screw mounting portion of a conventional fan fixing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fan 1b Flange part 2 Device housing substrate 3 Expansion type sound deadening box body 4 Intake guide member 6 Rotor blade mounting shaft part 7 Recessed groove part 13 Eddy current prevention member

Claims (7)

[Scope of utility model registration request] 1. An expansion type sound deadening box body is used, and a discharge side portion of the fan is connected to a suction side portion of the expansion type sound deadening box body.
Further, the fan fixing device is characterized in that the discharge side portion of the expansion type sound deadening box is fixedly connected to the device casing. 2. The fan fixing device according to claim 1, wherein the expansion type sound deadening box body is an elastic body having a vibration damping function. 3. The fan fixing device according to claim 1, wherein the fan is an axial fan, and an eddy current preventing member is fixed to a leeward side portion of the rotary mounting blade shaft portion. 4. The fan fixing device according to claim 1, wherein a suction guide member for collecting air is provided at a suction side portion of the fan. 5. The expansion-type sound-absorbing box body is provided with a recessed groove portion on a suction side wall portion, and a flange portion provided on a discharge side portion of the fan is fitted into the recessed groove portion. The fan fixing device described in 1. 6. The fan fixing device according to claim 3, wherein the eddy current prevention member has a conical shape, and the bottom surface thereof is a fixed installation surface. 7. The fan fixing device according to claim 4, wherein the suction guide member is formed in a cylindrical shape, and the suction side end portion thereof is gradually widened toward the outside.