JP3333856B2 - Electric fan and method of assembling the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fan assembling structure for a fan inside a refrigerator incorporated in a vending machine or a small electric fan used for a condensing unit cooling fan outside the refrigerator, and a method of assembling the fan. About.

[0002]

2. Description of the Related Art First, a conventional assembly structure of a small electric fan described above is illustrated in FIGS. In the drawing, 1 is a drive motor, 2 is a motor shaft, 3 is a fan blade,
Reference numeral 4 denotes a metal fan boss, and reference numeral 5 denotes a fan boss made of rubber (a molded product of synthetic rubber or the like having an appropriate elastic modulus).

[0003] 1) In the assembly structure shown in FIG.
A set screw 7 screwed to the fan boss 4 with the fan blades 3 mounted on the outer peripheral groove of the fan boss 4 via a rubber packing 6 for damping and fitted with the fan boss 4 on the motor shaft 2. Then, for example, a screw lock agent 8 is applied as means for preventing the set screw 7 from loosening. The rubber packing 6 has a function of suppressing amplification of fan noise due to transmission of vibration or the like from the drive motor 1 to the fan blades 3.

2) In FIG. 5, a fan blade 3 and a rubber plate 9 for vibration damping are superimposed on the rear end face of a metal fan boss 4 and fastened with a set screw 10 via a contact plate 4a. ,
Fan boss 4 is fixed by screws 7 stop in the same manner as FIG. 4 with respect to the motor shaft 2. 3) FIG. 6 shows a state in which the fan blades 3 are mounted on the circumference of a cylindrical rubber fan boss 5 made of a rubber molded product, and the motor shaft 2 is press-fitted into a shaft hole of the fan boss 5 and tightly fitted. Yes,
The diameter of the shaft hole formed in the center of the fan boss 5 is slightly smaller than the shaft diameter of the motor shaft 2 to give a tightening margin, and is fixed on the motor shaft using rubber elasticity.

4) FIG. 7 shows that the fan blades 3 are made of plastic and are integrally formed with a rubber fan boss 5, and
The rubber fan boss 5 has a plurality of radial slits 5a.
Previously put, the fan boss 5 while wearing on the axis of the motor shaft 2, the fan volume <br/> scan 5 is firmly fastened so as not to shift on the motor shaft using a C-shaped spring clamps 11 ing. 5) Figure 8 is a modification of FIG. 7, a rubber fan boss 5
The coil spring 12 is adopted as the fastening member.

[0006]

The structure of the prior art described above has the following problems. That is, 1) 4, in the structure of Figure 5, fan requires setscrew 7 to fix the metal fan Nbosu 4 when attached to the motor shaft at a predetermined position on the axis, further to the fan blades 3 The use of anti-vibration and vibration damping materials 6 and 9 increases the number of parts and the number of assembling steps, which increases the cost.

[0007] 2) On the other hand, in the assembly structure that employs a rubber fan boss 5 to the fan boss as shown in Figure 6-8, the fan volume <br/> separate part vibration damper because the scan itself has a damping function is no need, and set screw is also unnecessary, metal file of FIGS. 4 and 5
Structure as compared with the emission boss 4, although the assembly has the advantage of a simple, its positioning of the mounting position is not constant when the fan boss 5 is to be mounted on the motor shaft since it is cylindrical, in the fan assembly state Variations occur in the mounting positions of the fan blades. Further, when the motor shaft 2 is press-fitted into the rubber fan boss 5 or when the fitting surface between the fan boss 5 and the motor shaft 2 is locally displaced by an external force after assembly, the fan blade 3 Are eccentric with respect to the motor shaft 2 and the attitude of the blades is tilted. This causes the fan blades 3 to oscillate during operation, causing large vibration and noise.

The present invention has been made in view of the above points, and solves the above-described problems based on an electric fan employing a rubber fan boss as a fan boss. Provided is an electric fan assembly structure and an assembly method thereof, in which blades can be accurately positioned at a fixed position on a motor shaft and firmly mounted, and at the same time, surface contact of the fan blades due to external force can be suppressed well. With the goal.

[0009]

According to the present invention, there is provided an electric fan having a fan blade mounted on a rotating shaft of a drive motor via a fan boss made of a rubber molded product. integrally attached vanes on the outer periphery of the fan boss, and the press-fitted to the motor shaft to the shaft hole of the fan boss those interference fit, the fan boss cap-shaped and pear, the hole bottom wall surface of the axial hole The fan blade is configured to abut the tip of the motor shaft to position the mounting position of the fan blades , and the shaft hole of the fan boss is tapered toward the bottom of the hole.
It shall be formed as to become tapered hole (claim 1).

According to the present invention, the rotation of the drive motor is controlled.
The fan blades are mounted on the shaft via a rubber molded fan boss.
Electric fan with the fan blades out of the fan boss
It is connected to the circumference and integrated, and
The shaft is press-fitted and tightly fitted.
The boss has a cap shape, and the motor shaft is
To the mounting position of the fan blades.
And the cap end face of the fan boss
A small hole with a small diameter leading to the shaft hole shall be drilled.
2). In this case, the fan boss is attached to the motor shaft
Inject the adhesive through the small hole at the tip of the
Can be bonded to the motor shaft (claim 3).

Further , according to the present invention, the rotation of the drive motor is controlled.
Attach the fan blades via the rubber molded product boss on the spindle.
Electric fan with fan blades connected to the outer periphery of the boss.
And press-fit the motor shaft into the shaft hole of the boss and tighten it.
The boss has a cap shape
And abut the tip of the motor shaft against the bottom wall of the shaft hole.
It is configured to position the mounting position of the fan blade,
In the rear end surface of the boss, a slight gap is formed between the boss and the peripheral surface.
Install a metal washer that fits loosely on the motor shaft while leaving
(Claim 4). In this case,
Paste the outer peripheral area of the chassis with adhesive, and make the inner peripheral area non-adhesive
(Claim 5). Then, the inner peripheral surface area is
In order to adhere, facing the peripheral surface area without washer,
Forming a concave step including a ring-shaped groove on the rear end surface of the boss
(Claim 6).

According to the assembling method of the present invention, when assembling the electric fan, the motor shaft is inserted into the shaft hole of the fan boss with the small hole formed in the end face of the cap of the fan boss closed. Claim 7).

[0013]

With the above arrangement, when the assembly of the fan blades and the rubber fan boss is mounted on the motor shaft of the drive motor, the motor shaft is mounted on the bottom of the bottomed shaft hole opened in the cap-shaped fan boss. By fully inserting the fan blades until the ends abut, the mounting position of the fan blades on the motor shaft is uniquely determined without variation.

In this case, by forming the shaft hole as a tapered hole, a strong connection can be obtained between the motor shaft and the fan boss. Further, by previously sealing the small hole drilled in the cap tip when press-fitting the motor shaft to the shaft hole of the fan boss, air trapped in the shaft hole compresses files
Since expanding the axial hole of the down bosses, thereby insertion of the motor shaft with performed effortlessly, after the fan boss mounted whether the tip of the motor shaft through the small hole is fully inserted until it hits the bottom of the hole of the shaft hole Inspection can be easily performed visually or using a measuring jig. Further, in a state of mounting the fan <br/> boss on the motor shaft, if injecting adhesive (an instant adhesive) through the small hole, the motor shaft and the fan boss they are firmly bonded.

The metallic washer attached to the rear end face of the fan boss is always at a neutral position where it is loosely fitted on the motor shaft so that vibration of the motor is not transmitted, and an external force is applied after the fan is assembled. At this time, the inner peripheral edge of the washer hits the peripheral surface of the motor shaft to prevent deformation of the fan boss, and acts to suppress surface runout of the fan blade. When the external force disappears, the washer returns to the original neutral position due to the elasticity of the fan boss itself.

In this case, by attaching only the outer peripheral surface area of the washer to the rear end surface of the fan boss with an adhesive,
The anti-vibration and vibration control functions of the fan boss itself are not restrained or hindered by the washer. In addition, by forming a concave step on the rear end face of the fan boss facing the inner peripheral surface area of the washer, the inner peripheral surface area of the washer is bonded to the fan boss by sticking out the adhesive when attaching the washer. Adhesion can be prevented well.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the drawings of the embodiment, the same members corresponding to FIG. 6 are denoted by the same reference numerals. That is, in the illustrated embodiment, the base of the fan blades 3 is basically integrally connected to the outer periphery of a fan boss 5 formed as a rubber molded product as in FIG. It is mounted at a fixed position on the motor shaft 2.

Here, the fan boss 5 is formed as a cap-shaped molded product, and a shaft hole 5a is opened at the center of the shaft, leaving a bottom at the tip end side of the cap. The shaft hole 5a is set to a diameter slightly smaller than the shaft diameter d of the motor shaft 2 to give an interference, and is formed as a tapered hole tapering toward the hole bottom as shown in FIG. I have. In addition, the shaft hole 5a
Is not necessarily a tapered hole, but may be a straight hole. Further, a small-diameter small hole 5 communicating with the shaft hole 5a is provided on the end face of the cap of the fan boss 5 (the bottom of the shaft hole 5a).
b is open and the rear end face of the fan boss is shown in FIG.
In order to show the detailed structure, a metal washer 13 is overlaid and attached with an adhesive 14. The washer 13 is slightly larger than an inner diameter shaft diameter d of the motor shaft 2, it is loosely fitted to leave a slight gap Δd between the shaft peripheral surface while wearing the fan boss 5 on the motor shaft You. Here, only the outer peripheral surface area of the washer 13 is bonded to the fan boss 5 by the adhesive 14.
The inner peripheral surface area is kept in a non-adhered state with the rear end face of the fan boss 5. For this purpose, a concave step portion 5d including a ring-shaped groove 5c is formed at the center of the rear end face of the fan boss 5 facing the inner peripheral surface area of the washer 13, and the inner periphery of the washer 13 is formed by unnecessary protrusion of the adhesive 14. We try to prevent adhesion of the area.

Next, an operation procedure for mounting the fan blade assembly with the above configuration on the motor shaft 2 of the drive motor 1 will be described. First, FIG. 3A shows a state before the fan boss 5 is mounted on the motor shaft 2. In the fan assembly, a shaft hole 5 in which the tip of the motor shaft 2 is opened to the fan boss 5 from the illustrated position.
a until it comes into contact with the bottom of the hole and press-fitted. Then, the adhesive 15 is injected into the shaft hole 5a from the small hole 5b opened on the end face of the cap, and the motor shaft 2 and the fan boss 5 are bonded together. Assembled state shown. In this assembled state, the mounting position of the fan boss 5 with respect to the motor shaft 2, that is, the mounting position of the fan blades 3 on the motor shaft is uniquely determined.

Further, in this case, in order to easily press-fit the motor shaft 2, the fan boss 5 as shown in FIG.
The motor shaft 2 is inserted through the shaft hole 5 from the rear end face side of the fan boss 5 in a state where the small hole 5b opened on the end face of the cap is sealed with a sealing jig 16 (a ready-made one having a smooth surface such as a surface plate may be used).
Press into a. As a result, the air sealed in the shaft hole 5a is compressed using the motor shaft 2 as a piston, and the air pressure widens the shaft hole 5a, so that the motor shaft 2 can be easily inserted. When the sealing jig 16 is removed when the motor shaft 2 is fully pushed in, the air sealed in the shaft hole 5a escapes through the small hole 5b so that the fan boss 5 comes into close contact with the peripheral surface of the motor shaft 2. Become.

In this assembling step, the position of the end face of the motor shaft 2 is visually checked through a small hole 5b on the end face of the cap or by using a measuring jig, so that the fan boss 5 is mounted at a fixed position with respect to the motor shaft 2. Can be easily checked. On the other hand, in the assembled state of FIGS. 1 and 2 in which a fan is mounted on the motor shaft 2, the inner peripheral edge of the metal washer 13 attached to the rear end face of the fan boss 5 is
Are loosely fitted to each other with a slight gap Δd between them.
Thus, the fan blades 3, when the fan boss 5 by an external force applied to the fan boss 5 is a fan blade 3 deforms when you incline the axial center of the motor shaft 2, the inner peripheral edge of the washer 13 abuts against the outer peripheral surface of the motor shaft 2 To prevent further deformation. When the external force disappears, the fan boss 5 itself is elastically restored, and the washer 13 returns to the original neutral position.
As a result, the fan blades 3 do not come into contact with the surface during operation, and the occurrence of abnormal vibration and noise caused by the surface run-out can be prevented.

[0022]

As described above, according to the present invention, the following practical effects can be obtained in terms of assemblability and reliability of the electric fan. 1) By making the fan boss made of rubber molded product into a cap shape, when the fan boss is mounted on the motor shaft of the drive motor based on the end face of the cap, the tip of the motor shaft is closed.
§ the down bosses until it hits the bottom hole of the opened shaft hole by press-fitting to the full assembly of the simplification to be able to correctly position the fan blades in place can be achieved.

2) By drilling a small hole in the end face of the cap of the fan boss, whether the fan boss is mounted at a predetermined position is visually observed or measured through the small hole with the fan boss mounted on the motor shaft. In addition to this, the adhesive can be easily injected into the fan boss and the motor shaft by using an adhesive injected from the small hole without using a special fastening part. In addition, by closing the small hole when inserting the motor shaft into the shaft hole of the fan boss, the shaft hole can be expanded by the air pressure sealed in the shaft hole, and the shaft can be easily inserted.

[0024] 3) by which loosely fitted to the motor shaft to the rear end surface of the fan boss deposited a metal washer, the deformation of the fan boss as the washer stopper when an external force is applied, the surface of the fan blades due to the deviation Shaking can be prevented, and abnormal vibration and noise caused by this can be prevented.

[Brief description of the drawings]

FIG. 1 is an assembly structure diagram of an electric fan according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing a detailed structure of a main part in FIG.

FIG. 3 is an explanatory view of an assembling procedure of the embodiment of the present invention;
(A) is a diagram showing a state before the fan boss is mounted on the motor shaft, and (b) is a diagram showing a state in which the motor shaft is being inserted into the fan boss.

FIG. 4 is a conventional fan assembly structure in which a metal fan boss is used as the fan boss.

FIG. 5 is a conventional assembly structure diagram different from FIG.

FIG. 6 is a conventional fan assembly structure in which a rubber fan boss is used as the fan boss.

FIGS. 7A and 7B are views showing a conventional fan assembly structure in which a fastening member is combined with a rubber fan boss, wherein FIG. 7A is a side sectional view and FIG.

FIG. 8 is a conventional assembly structure diagram different from FIG. 7;
Is a side sectional view, and (b) is a sectional view of a coil spring as a fastening member in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 drive motor 2 motor shaft 3 fan blade 5 rubber fan boss 5 a shaft hole (tapered hole) 5 b small hole 5 c ring-shaped groove 5 d concave step 13 metal washer 14, 15 adhesive 16 sealing jig

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Jikken 47-25000 (JP, Y1) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04D 29/34 F04D 25/08 305 F04D 29 / 60 F04D 29/04

Claims (7)

(57) [Claims] Of 1. A rubber molded article on a rotating shaft of the drive motor fan
An electric fan equipped with a fan blade through the down bosses, the fan blades integrally attached to the outer periphery of the fan boss, and by press-fitting the motor shaft to the shaft hole of the fan boss in those interference fit, the The fan boss is shaped as a cap, and the tip of the motor shaft is abutted against the bottom wall of the shaft hole to position the fan blades .
One, the shaft hole of the fan boss tapers toward the bottom of the hole.
An electric fan formed as a tapered hole . 2. A rubber molded product filed on a rotating shaft of a drive motor.
This is an electric fan with fan blades
And integrate the fan blades with the outer periphery of the fan boss
And press the motor shaft into the shaft hole of the fan boss and tighten it.
In the fitting, the fan boss has a cap shape.
None, the end of the motor shaft is abutted against the bottom wall of the shaft hole
To position the fan blades on the
The small diameter that leads to the shaft hole on the end face of the cap of the fan boss
An electric fan characterized by having perforated small holes. 3. The electric fan according to claim 2, wherein
With the fan boss attached to the shaft, from the small hole at the tip
Adhesive was injected to bond the fan boss and motor shaft
An electric fan, characterized in that: 4. A rubber molded product on a rotating shaft of a drive motor.
This is an electric fan with fan blades
And integrate the fan blades with the outer periphery of the fan boss
And press the motor shaft into the shaft hole of the fan boss and tighten it.
In the fitting, the fan boss has a cap shape.
None, the end of the motor shaft is abutted against the bottom wall of the shaft hole
To position the fan blades on the
A slight difference between the rear end surface of the fan boss and the shaft peripheral surface.
Equipped with a metal washer that fits loosely on the motor shaft leaving a gap.
An electric fan characterized by being worn . 5. The electric fan according to claim 4, wherein
Paste the washer's outer peripheral surface area with the adhesive with the adhesive,
Dynamic fan collector, characterized in that the inner peripheral surface area and a non-adhesive. 6. The electric fan according to claim 5, wax
A ring is attached to the rear end face of the fan boss, facing the inner peripheral surface area of the chassis.
An electric fan, wherein a concave step portion including a groove is formed . 7. When assembling the electric fan according to claim 2.
The small hole drilled in the end face of the fan boss cap
Insert the motor shaft into the shaft hole of the fan boss in this state.
How to assemble an electric fan .