JP2002138994A - Fixing structure of fan and motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing structure of a fan and a motor capable of suppressing the transmission of motor vibration to the fan and suppressing a sound pressure of the fan. SOLUTION: In this fixing structure of the fan and the motor constituted such that a shaft 310 of the motor 300 is inserted into a fitting hole 230 passing through in the direction of a rotary shaft provided in a central part of the fan 200, a fixing member 400 is provided in a tip part 314 of the shaft 310, and the fan 200 is restricted in the direction of rotary shaft, a vibration suppressing part 110 for suppressing the transmission of vibration from the motor 300 is provided in at least either of between a fixing face 233 and the fixing member 400 and between a fan receive face 313 and a positioning face 232. This vibration suppressing part 110 is formed as a clearance part 110a or as a damping member 110b having the elasticity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a structure for fixing a fan and a motor, which constitutes a blower for blowing air to a heat exchanger in a heat pump cycle, for example.

[0002]

2. Description of the Related Art As shown in FIG. 9, a conventional structure for fixing a fan and a motor constituting a blower is such that a shaft 310 of a motor 300 is passed through a fitting hole 230 provided at the center of the fan 200. The tip of the shaft 310 is fixed with a nut 400.

[0003] Specifically, the shaft 310 is provided with a fan receiving surface 313 orthogonal to the longitudinal direction, an engaging surface 311 a parallel to the longitudinal direction, and a screw portion (male screw) 315. The fitting hole 230 is provided with an engagement surface 231a that engages with the engagement surface 311a of the shaft 310, a positioning surface 232 orthogonal to the rotation axis, and a fixed surface 233.
Then, the fan 200 is mutually locked with the shaft 310 in the rotational direction by the engagement surfaces 231a and 311a. Further, the fan 200 is provided on the fan receiving surface 313 of the shaft 310.
And the nut 400
Are screwed up to the fixing surface 233 of the fan 200 so that the shaft 310 and the fan 200 are also fixed in the rotation axis direction.

[0004]

However, since the fan 200 is rigidly fixed to the motor 300 by the nut 400, the vibration of the motor 300 is transmitted to the fan 200 as it is, and a peak of sound pressure is generated by resonance. There is a problem that the sound pressure level becomes high.

An object of the present invention is to provide a fixing structure between a fan and a motor which can suppress the propagation of motor vibration to the fan and suppress the fan sound pressure in view of the above problems.

[0006]

The present invention employs the following technical means to achieve the above object.

According to the first aspect of the present invention, the fan (20
The shaft (310) of the motor (300) is inserted into a fitting hole (230) penetrating in the direction of the rotation axis provided at the center of the motor (300).
Through the fitting hole (230) and the engaging portions (231, 311) provided in the shaft (310) in the rotational direction, and a fan provided in an intermediate portion of the shaft (310). The fan (20) is received against the receiving surface (313).
The tip of the shaft (310) protruding from the fixed surface (233) provided on the shaft (310) penetrating side of the fan (200) is brought into contact with the positioning surface (232) provided on the shaft (310) fitting side of the fan (200). A fixing member (400) is provided in the part (314), the fan (200) is restricted in the rotation axis direction, and a space between the fixing surface (233) and the fixing member (400) and the fan receiving surface are provided. At least one between the position (313) and the positioning surface (232) has a vibration suppression unit (11) for suppressing the propagation of vibration from the motor (300).
0) is provided.

[0008] The vibration suppressing portion (110), as in the second aspect of the present invention, sets the distance (X) between the fan receiving surface (313) and the fixing member (400) to the positioning surface (23).
The gap (110a) formed is made larger than the spacing dimension (Y) between 2) and the fixing surface (233).

Specifically, as in the third aspect of the present invention, the fixing member (400) is a nut (400), and a screw portion (315) is formed on the tip (314) side. Then, at a position where the fan receiving surface (313) and the positioning surface (232) are in contact with each other, the nut (400) is screwed into the screw portion (31).
When screwed into 5), the fixing surface (23) of the nut (400)
The screwing end position on the 3) side is set between the distal end (314) and the fixing surface (233).

In this case, the nut (400) is provided with a screw hole (401) penetrating therethrough, and the nut receiving surface (313) and the positioning surface (232) are provided. Screw part (315) at the position where
Is preferably provided so as to be shorter than the dimension from the tip (314) to the fixing surface (233).

According to the first to fourth aspects of the present invention, a gap () is provided between the fan receiving surface (313) and the positioning surface (232) or between the fixing surface (233) and the nut (400). 110a) can be formed, and the vibration from the motor 300 is directly propagated by the gap portion (110a) without rigidly fixing the fan 200 between the fan receiving surface (313) and the nut 400 as a fixing member. Since this is suppressed, resonance can be suppressed, and the sound pressure level can be reduced.

According to the fifth aspect of the present invention, the vibration suppressing portion (110) is provided with an elastic damping member (110).
The vibration from the motor 300 can be absorbed by the vibration damping member (110b) and the resonance can be suppressed, so that the sound pressure level can be reduced.

The reference numerals in parentheses of the above means indicate the correspondence with the specific means described in the embodiments described later.

[0014]

(First Embodiment) FIG. 1 shows a first embodiment of the present invention. The present invention is applied to, for example, a blower 100 that blows air to a heat exchanger in a heat pump cycle in a household water heater. Specifically, a refrigerant in an evaporator as a heat exchanger constituting a heat pump cycle blows air for absorbing heat, and is disposed together with the evaporator in an outdoor unit.

As shown in FIG. 1A, a blower 100 has a shaft 200 of a motor 300 penetrating a fan 200 and a fixing member 400 provided therein.
00 drives the fan 200 to blow air. In the fan 200, air is blown to the side opposite to the motor (rightward) shown in FIG.

As shown in FIG. 1B, the shaft 310
The fan receiving surface 313 orthogonal to the longitudinal direction
Is provided to cut the shaft 310 by a predetermined amount,
Further, an engagement portion 311 that forms a plane from the cut lower end portion toward the tip end portion 314 is provided. Thus, the cross-sectional shape of the engaging portion 311 is a crescent shape as shown in FIG. Further, the tip portion 314 side is formed smaller than the outer diameter of the shaft in the engagement portion 311 region, and a screw portion 315 serving as a male screw is formed.
A nut 400 as a fixing member is screwed. The nut 400 is a so-called hexagonal nut formed so that a screw hole 401 serving as a female screw passes through the center.

On the other hand, the fan 200 has a plurality of blades 210 provided on the outer periphery of the boss 220, and a fitting hole 230 through which the shaft 310 passes is provided at the center. The shaft fitting side of the fitting hole 230 is the shaft 3
Positioning surface 232 in contact with ten fan receiving surfaces 313
Is provided as a plane perpendicular to the rotation axis so as to be built up in the circular hole, and forms a plane from the rotation shaft side end of the positioning surface 232 toward the tip end 314 side of the shaft 310. A part 231 is provided. As a result, the cross-sectional shape of the fitting hole 230 becomes a crescent shape as shown in FIG.
The engagement portions 231 and 311 are locked to each other in the rotation direction. Further, a fixing surface 233 orthogonal to the rotation axis is formed on the shaft penetrating side facing the shaft fitting side of the fitting hole 230.

After the shaft 310 of the motor 300 is passed through the fitting hole 230 of the fan 200 so that the engaging portions 231 and 311 engage with each other, the fan receiving surface 3
13 at the position where the positioning surface 232 abuts,
The length of 5 is shorter than the dimension from the tip 314 to the fixing surface 233. That is, in a state where the nut 400 is screwed into the screw portion 315 and tightened, the distance X between the fan receiving surface 313 and the nut 400 is set to be larger than the distance Y between the positioning surface 232 and the fixed surface 233. This dimensional difference is formed as a gap 110a as a vibration suppressing portion. (Actually, since the fan 200 is movable between the fan receiving surface 313 and the nut 400, the gap 110a is
13 and between the positioning surface 232, and that portion is also taken into consideration. Next, the operation based on the above configuration will be described. The shaft 310 of the motor 300 is rotationally driven by a DC power supply (not shown), and the driving torque of the shaft 310 is transmitted to the fan 200 as it is by the engaging portions 311 and 231, and the fan 200 rotates to blow air to an evaporator (not shown). When the fan 200 is rotating, the blade 210 receives a thrust in the direction opposite to the blowing direction, so that the fan 20
0 comes into contact with the positioning surface 232, and the fixed surface 2
33 and a nut 400, a gap 110 a is formed between the nut 400 and the fixing surface 233, that is, the fan 2.
00 rotates well without being rigidly fixed in the direction of the rotation axis.

As a result, the vibration from the motor 300 is suppressed from being directly transmitted to the fan 200, so that the resonance can be suppressed and the sound pressure level of the fan 200 can be reduced.

FIG. 2 is a graph comparing sound pressure levels with respect to the number of fan revolutions of the present invention and the conventional art. In this example, the fan 200 has an outer diameter of 400 mm,
Three-bladed type, motor 300 has an outer diameter of 94 mm,
8 Watt specification, it is placed in the outdoor unit as a blower 100 together with the evaporator, and this outdoor unit is set on the floor in the soundproof room, at a height of 1 m from the floor and at a position 1 m away from the outdoor unit. A microphone is installed and the sound pressure level is measured.

In the present invention, the occurrence of a sound pressure peak due to resonance as in the prior art is suppressed, and has a substantially linear characteristic with respect to the fan rotation speed, and the sound pressure level is reduced. I have.

Further, in the present embodiment, it is possible to substantially cope with the prior art by shortening the formation length of the screw portion 315, and there is no need for a new capital investment.

Further, since the nut 400 is fixed away from the fixing surface 233, when the motor 300 starts rotating,
When the rotational direction of the fan 200 viewed from the tip 314 is set to the right, it is unlikely to be affected by the inertial force in the reverse rotation direction that also has the mass of the fan 200 due to the frictional force with the fixed surface 233. In the technique, a nut with a left-handed thread is used in some cases to prevent the nut 400 from being loosened due to the inertial force. However, in the present embodiment, a standard right-handed nut 400 is used. it can.

The air blowing direction of the fan 200 is not limited to the direction opposite to the motor (right direction) as shown in FIG. 1, but may be the direction of air blowing to the motor side (left direction). In this case, the fixing surface 233 and the nut 400 come into contact with each other by the thrust, but are not rigidly fixed to the last, so that the direct propagation of the vibration from the motor 300 is suppressed.

(Second Embodiment) FIG. 3 shows a second embodiment. In the second embodiment, the form of the vibration suppressing unit 110 is changed from that of the first embodiment.

Here, the gap 11 of the first embodiment is used.
0a, a vibration damping member 110b made of an elastic rubber material
To prevent the fixing surface 233 from being rigidly fixed by the nut 400.

Thus, the vibration from the motor 300 can be absorbed and the resonance can be suppressed, so that the sound pressure level can be reduced.

(Other Embodiments) Other embodiments are shown in FIGS.

FIGS. 4 to 7 show modifications of the first embodiment, which are variations of the method of forming the gap 110a.

FIG. 4 shows a first modification in which a cylindrical collar 500 is interposed on the outer periphery of the screw portion 315. A collar having a predetermined length L between the threaded root portion 316 and the nut 400 is shown. 500 are provided to form the gap 110a.

FIG. 5 shows a second modification in which the nut 400 is a so-called cap nut 400a in which one of the screwing directions is closed, and the screwing stops at the tip 314 and the closed side of the cap nut 400a. Thus, a gap 110a is formed.

According to the first and second modifications, the effect of reducing the sound pressure level can be obtained by utilizing the conventional motor as it is.

FIG. 6 shows a third modification in which the nut 400 is replaced with a press-fit joint 410 and the screw portion 314 is replaced with a tapered portion 317. The gap 110a is adjusted by adjusting the press-fit stop position of the joint 410. Is formed.

Thus, the formation of the screw portion 315 becomes unnecessary, and the shaft 310 can be simplified.

FIG. 7 shows a fourth modification in which the nut 400 is replaced with a so-called C-ring 420 and a screw portion 314 is formed.
May be replaced with the groove 318, and the gap 110a may be formed by adjusting the set position of the groove 318.

FIG. 8 shows a fifth modification of the second embodiment, in which the vibration damping member 110b is provided on the fan receiving surface 31.
3 and the positioning surface 232. Thereby, the vibration from the motor 300 can be further absorbed, and the sound pressure level due to resonance can be reduced.

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment of the present invention, wherein FIG. 1A is an overall configuration diagram, FIG. 1B is a cross-sectional view of an A section, and FIG. 1C is a cross-sectional view of a BB section.

FIG. 2 is a graph showing a comparison of a sound pressure level with respect to a fan speed according to the present invention and a conventional technique.

FIG. 3 is a sectional view showing a second embodiment of the present invention.

FIG. 4 is a cross-sectional view showing Modification Example 1 of the first embodiment.

FIG. 5 is a cross-sectional view showing Modification 2 of the first embodiment.

FIG. 6 is a cross-sectional view showing Modification Example 3 of the first embodiment.

FIGS. 7A and 7B are a cross-sectional view and a perspective view showing Modification 4 of the first embodiment.

FIG. 8 is a sectional view showing Modification Example 5 of the second embodiment.

FIGS. 9A and 9B show the prior art, wherein FIG. 9A is an overall configuration diagram, FIG. 9B is a cross-sectional view of a portion C, and FIG.

[Explanation of symbols]

 110 Vibration suppression part 110a Gap part 110b Vibration suppression member 200 Fan 230 Fitting hole 231 Engagement part 232 Positioning surface 233 Fixing surface 300 Motor 310 Shaft 311 Engagement part 313 Fan receiving surface 314 Tip part 315 Screw part 400 Nut (fixing member) ) 401 screw hole

Claims (5)

[Claims] 1. A center hole of a fan (200) is provided with a fitting hole (230) penetrating in a direction of a rotation axis, and a shaft (310) of a motor (300) passes through the fitting hole (230). The fitting hole (230) and the shaft (310) are provided with engaging portions (231, 311) which are locked to each other in a rotating direction, and a fan support provided at an intermediate portion of the shaft (310). A positioning surface (232) provided on the shaft (310) fitting side of the fan (200) is in contact with the surface (313), and a fixing provided on the shaft (310) penetrating side of the fan (200). A fixing member (400) is attached to the tip (314) of the shaft (310) projecting from the surface (233).
Is provided, the fan (200) is restricted in the rotation axis direction, and the space between the fixing surface (233) and the fixing member (400) and the fan receiving surface (313) are provided.
A structure for fixing a fan and a motor, wherein a vibration suppression unit (110) for suppressing propagation of vibration from the motor (300) is provided on at least one of the motor and the positioning surface (232). . 2. The vibration suppressing section (110) sets the distance (X) between the fan receiving surface (313) and the fixing member (400) to the positioning surface (232) and the fixing surface (233). The fixing structure according to claim 1, wherein the gap (110a) is formed by making the distance dimension (Y) larger than the gap dimension (Y). 3. The fixing member (400) includes a nut (40).
0), a screw portion (315) is formed on the tip portion (314) side, and the fan receiving surface (313) and the positioning surface (232) are formed.
The nut (400) is screwed into the screw portion (315) at a position where the nut (400) is brought into contact with the nut (400). 314) and the fixing surface (23)
The fixing structure of a fan and a motor according to claim 2, wherein the fixing structure is provided so as to be located between the fan and the motor. 4. The nut (400) is provided with a threaded hole (401) penetrating therethrough, the fan receiving surface (313) and the positioning surface (232).
And the length of the screw part (315) is provided to be shorter than the dimension from the tip part (314) to the fixing surface (233). A fixing structure for the fan and the motor according to claim 3. 5. The structure for fixing a fan and a motor according to claim 1, wherein said vibration suppressing portion (110) is a vibration damping member (110b) having elasticity.