JPH0314941Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fan motor, and particularly to a structure for externally fixing the fan to the rotating shaft of the motor.
The present invention relates to a device that is effective when used as a fan motor for a radiator mounted on a vehicle such as an automobile.

[Conventional technology]

In conventional fan motors of this kind, when the fan is externally fixed to the rotating shaft of the motor, a fixing structure as shown in FIG. 3 is generally employed.

That is, in FIG. 3, one end of the rotating shaft 2 of the motor 1 is formed with a one-sided or two-sided flattened part 3 and a male threaded part 4, and a central part of a synthetic resin fan 5 is formed. A boss member 6 made of aluminum die-casting is integrally fixed to the. The fan 5 attaches its boss member 6 to the rotating shaft 2 in the planar processing section 3.
The nut 7 is screwed onto the male threaded portion 4 and tightened to be fixed.

[The problem that the idea attempts to solve]

However, such a fan fixing structure for a fan motor has the following problems.

(1) Although the rotating shaft and the fan boss member are fitted with a clearance, due to dimensional variations in parts machining,
Because clearance occurs around 0.05 to 0.2 mm,
Due to this clearance, there is a risk that the fan may be fixed eccentrically with respect to the rotating shaft, or the fan may be fixed tilted, which may cause an imbalance in the fan's rotational balance or vibration.

(2) In order to minimize the aforementioned eccentricity and tilted mounting, and to ensure strength at the fitting part between the rotating shaft and fan boss part, it is necessary to set a relatively long fitting allowance. Therefore,
The overall length of the fan motor becomes longer.

The purpose of this invention is to solve the above-mentioned problems of the conventional technology, suppress the overall length of the fan motor, prevent the rotational balance of the fan from being unbalanced and run out, and properly fix the fan to the rotating shaft. Our goal is to provide a fan motor that can

[Means to solve the problem]

The fan motor according to the present invention includes a rotary shaft 8, which is rotatably supported in a case 9 with one end 8a protruding, and has an armature 11 fixed to an intermediate portion in the case 9, and a rotary shaft 8 that has mechanical strength. It is equipped with a plate 15 integrally molded in a rotationally symmetrical shape using a metal material with a large diameter, and a fan 21 integrally molded using resin, and the plate 15 has a press-fit hole 16 at its center. is aligned with the plate 15 itself, and the press-fit hole 16 has a chamfered portion 16a at one end and a bossed portion 16 at the other end.
Further, a plurality of screw holes 17 are formed in the plate 15, and each screw hole 17 is arranged outside the press-fit hole 16 and opened parallel to the axial direction. A boss shaft 22 is disposed concentrically with the fan 21 at the plate 15.
The boss portion 22 has a light press-fit hole 23 that is slightly smaller than the outer diameter of the rotating shaft 8.
1 itself, and a hole larger than the outer diameter of the bossed part 16b is formed at the opening edge of the light press-fit hole 23 of the boss part 22. 22 has a screw insertion hole 24
A plurality of screw holes 17 of the plate 15 are arranged to face each other and are opened parallel to the axial direction, and one end 8a of the rotary shaft 8 protruding from the case 9 is press-fitted into the plate 15. The plate 15 is inserted into the hole 16 from the chamfered portion 16a side and press-fitted so that its tip protrudes outward in the axial direction from the bossed portion 16b.
is fixed, and the protruding end 8a from the plate 15 at one end protruding from the case 9 of the rotary shaft 8 is inserted into the light press-fit hole 23 of the fan 21 using the resin itself forming the boss portion 22. is press-fitted so that a tight fitting state is created due to the elasticity of The fan 21 and the plate 15 are connected to each other by screws 25.
are inserted into each of the screw insertion holes 24 and screwed into each of the screw holes 17, thereby being fastened.

[Effect]

According to the above-described means, since the plate 15 is press-fitted and fixed to the rotating shaft 8, there is no radial clearance between the plate 15 and the rotating shaft 8. Further, since the protruding end 8a of the rotating shaft 8 is lightly press-fitted into the light press-fit hole 23 of the fan 21,
There is no radial clearance between the fan 21 and the rotating shaft. Therefore, there is no clearance in the radial direction between the rotating shaft 8, the plate 15, and the fan 21, and it is inevitable that the three members will be integrally connected with their axes accurately aligned. Become.

Since the fan 21 is fastened with the screws 25 disposed outside the rotating shaft 8 with its boss 22 in contact with the plate 15, the rotating shaft 8, the plate 15, and the fan 21 are fastened together as described above. Coupled with the fact that the three-way axis alignment with the fan 21 is ensured, there is no risk that the boss part 22 will be tilted and fixed to the exterior with respect to the rotating shaft 8, and this will prevent the fan 21 from becoming unbalanced. The occurrence of rotational runout is completely eliminated.

〔Example〕

FIG. 1 is a longitudinal sectional view showing a fan motor which is an embodiment of the present invention, and FIG. 2 is a front view of a plate.

In this embodiment, the fan motor includes a rotating shaft 8, which is rotatably supported within a case 9 by a pair of bearings 10, 10. An armature 11 and a commutator 12 are externally fixed to the intermediate portion of the rotating shaft 8, and the armature 11 has a plurality of magnets 13 arranged at approximately equal intervals on the inner circumference of the case 9.
In addition, the commutator 12 is configured to be able to rotate in sliding contact with a brush 14 held within the case 9.

One end of the rotating shaft 8 projects outward from one end surface of the case 9, and a plate 15 is press-fitted into the projecting end 8a. A substantially conical holding recess 19 is recessed in the end surface of the rotation shaft 8 opposite to the plate fixed end, and this recess 19 is an end bracket 9a integrated into the case 9 so as to close the opening. It is arranged so as to face a through hole 20 opened at the center of the end face.

The plate 15 is integrally formed by stamping and press processing using a metal material with high mechanical strength such as iron, and as shown in FIG.
It is formed into an approximately disk shape. A press-fit hole 16 is formed in the center of the plate 15 and is aligned with the axis of the plate 15 itself. Rotating shaft 8 of press-fit hole 16
A chamfered portion 16a is formed at the end on the press-fitting side, and this chamfered portion 16a allows smooth press-fitting. A bossed portion 16b is formed at the other end of the press-fit hole 16, and the bossed portion 16b provides a long fitting allowance and ensures sufficient press-fitting strength.

A plurality of screw holes 17 are provided on the periphery of the plate 15.
They are opened at equal intervals in the circumferential direction, and window holes 18 are opened between adjacent screw holes 17, 17, respectively.

When press-fitting and fixing the plate 15 to the rotary shaft 8, after aligning one end of the rotary shaft 8 with the press-fit hole 16 of the plate 15, press the presser recess 19 formed on the other end surface of the rotary shaft 8 and press the pressing device (not shown). ), one end of the rotating shaft 8 is inserted into the press-fit hole 1 of the plate 15.
6 and press-fit it relatively. At this time, press-fit hole 16
Since the chamfered portion 16a is provided on the plate 15, the rotary shaft 8 is smoothly press-fitted into the press-fit hole 16 of the plate 15. In addition, since the press-fitting hole 16 is formed with a boss-extruded portion 16b so that the fitting distance is long, the rotating shaft 8 is strongly fixed to the plate 15, and the rotating shaft 8 and the plate 15 are located at a high height. They become orthogonal to each other with precision. In this press-fitting state, one end 8a of the rotating shaft 8 passes through the plate 15 and protrudes from the bossed portion 16b.

A fan 21 integrally molded from synthetic resin is fastened to the plate 15 press-fitted onto the rotating shaft 8 with screws 25, with the end face of the boss portion 22 of the fan 21 in contact with the plate 15.

That is, the boss portion 22 is formed simultaneously with the fan 21 into a substantially disk shape slightly larger than the plate 15, and a light press-fit hole 23, which is slightly smaller than the diameter of the rotating shaft 8, is formed in the center of the boss portion 22 and the fan 21 itself. Opened and centered. A plurality of screw insertion holes 24 are provided on the outer periphery of the boss portion 22 and are arranged to correspond to the screw holes 17 of the plate 15, respectively.

When fixing the fan 21 to the rotating shaft 8,
One end surface of the boss section 22 is brought into contact with the end surface of the plate 15 by lightly press-fitting the light press-fit hole 23 of the boss section 22 into the portion protruding from the plate 15 to the outside. At this time, since the boss portion 22 is made of synthetic resin, light press-fitting can be easily performed, and a tight fit is created due to the elasticity of the resin itself forming the boss portion 22. . In the state where the fan 21 is lightly press-fitted into the rotating shaft 8, the boss portion 22 of the fan 21 is inserted into each insertion hole 24.
are aligned with each screw hole 17 of plate 15, respectively. Subsequently, the screws 25 are inserted into the respective insertion holes 24 and screwed into the screw holes 17, whereby the boss portion 22 of the fan 21 is fastened to the plate 15.

In addition, in Fig. 1, 26 indicates the case 9 and the fan 21.
The labyrinth seal portion 27 provided between the surfaces facing the boss portion 22 is a cap that is placed over the end bracket 9a so as to close the through hole 20 of the end bracket 9a.
This prevents external sewage and dust from entering the motor.

In the fan motor having the above configuration, power is supplied from the bracket 14 to the commutator 12, so that the armature 11 is connected to the magnet 13.
The magnetic field is turned off to rotate the rotary shaft 8, and the rotation of the fan 21 externally fixed to the rotary shaft 8 generates a flow of air in a direction parallel to the shaft center.

[Effect of idea]

Since the plate 15 is press-fitted and fixed to the rotating shaft 8, there is no radial clearance between the plate 15 and the rotating shaft 8. Also, Juan 21
is the protruding end portion 8a of the rotating shaft 8 from the plate 15 when the boss portion 22 is in contact with the plate 15.
Since the screws 25 are placed outside the light press-fit hole 23 and the rotation shaft 8, the plate 15, and the fan 21 are
There is no clearance between them in the radial direction. Therefore, there is no clearance in the radial direction between the rotating shaft 8, the plate 15, and the fan 21. Since there is no clearance, the boss portion 2 is
There is no danger that the rotational balance 2 will be eccentrically or tilted and fixed to the exterior, and the cause of improper rotational balance and rotational runout will be eliminated.

Furthermore, since the fan boss portion 22 is fastened with the screw 25 while in contact with the end surface of the plate 15, the fan 21 can be fixed perpendicularly to the rotating shaft 8 with high precision. Become. Therefore, the fan 21 that occurs when the fan 21 is externally fixed to the rotating shaft 8 at an angle
This makes it possible to more reliably prevent runout.

By press-fitting the plate 15 and the boss portion 22 of the fan 21 into the rotating shaft 8, it is possible to avoid the risk of eccentricity or tilted mounting. It is no longer necessary to set the motor to a long value, and therefore the total length of the motor can be shortened.

By providing the chamfered portion 16a in the press-fit hole 16 of the plate 15, the rotating shaft 8 can be press-fitted into the press-fit hole 16 smoothly and accurately.

By providing the bossed portion 16b in the press-fit hole 16 in the plate 15, the contact length at the press-fit location can be increased without increasing the wall thickness of the plate 15, which further improves the effect of preventing eccentricity and inclination. can do.

Due to its nature, the rotary shaft 8 of the motor is normally manufactured with extremely high precision, and this high processing precision can be utilized as is for press-fitting and fixing the rotary shaft 8 and the plate 15. can be maintained at an extremely high level, and cost performance can be improved.

Since it is possible to eliminate the flat surface processing part and the external thread part on the rotating shaft 8, not only can the number of processing steps be reduced, but also it is possible to avoid the accuracy of the rotating shaft 8 from being impaired by such processing. Moreover, the total length of the rotating shaft 8 can be shortened by the tightening margin between the male threaded portion and the nut.

By the way, if a screw member is used to fasten a resin member, there is a high risk that the strength will be insufficient. However, in the present invention, since the plate 15 is made of a metal material, it is possible to open the screw hole 17 and use screws 25 as a fastening means.

In addition, the insertion hole 24 of the fan 21 through which the screw 25 is inserted is provided with alignment with the screw hole 17 and screw 25.
Since the insertion hole 24 requires a margin for the insertion of the fan 21 and the rotary shaft 8, alignment of the fan 21 and the rotary shaft 8 cannot be ensured. However, the axis alignment between the fan 21 and the rotating shaft 8 is difficult.
1 and the rotating shaft 8 are lightly press-fitted. In other words, by employing light press-fitting between the fan 21 and the rotating shaft 8, it becomes possible to employ a fastening means using the screws 25.

By opening the screw holes 17 in the plate 15, it becomes possible to fix the fan 21 to the plate 15 from the outside in the axial direction, that is, from the opposite side of the motor. By fastening with the screws 25, the plate 15 and the fan 21 are tightly coupled, so that high bonding strength can be obtained over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a fan motor which is an embodiment of the present invention, FIG. 2 is a side view of a plate, and FIG. 3 is a partially cutaway front view showing a conventional example. 8...Rotating shaft, 9...Case, 10...Bearing,
11... Armature, 12... Commutator, 13... Magnet, 14... Brush, 15
... Plate, 16 ... Press-fit hole, 17 ... Screw hole, 18 ... Window hole, 19 ... Pressing recess, 20 ...
...Through hole, 21...Fan, 22...Boss part, 23
... Light press-fit hole, 24 ... Screw insertion hole, 25 ... Screw.

Claims (1)

[Claims for Utility Model Registration] A rotary shaft 8 whose one end portion 8a is protruded and rotatably supported within a case 9, and an armature 11 fixed to an intermediate portion within the case 9, and a mechanical strength It is equipped with a plate 15 integrally molded in a rotationally symmetrical shape using a metal material with a large diameter, and a fan 21 integrally molded using resin, and the plate 15 has a press-fit hole 16 at its center. is aligned with the plate 15 itself, and the press-fit hole 16 has a chamfered portion 16a at one end and a bossed portion 16 at the other end.
Further, a plurality of screw holes 17 are formed in the plate 15, and each screw hole 17 is arranged outside the press-fit hole 16 and opened parallel to the axial direction. A boss portion 22 is arranged concentrically with the fan 21 at the portion of the plate 15.
The boss portion 22 has a light press-fit hole 23 that is slightly smaller than the outer diameter of the rotating shaft 8.
1 itself, and a hole larger than the outer diameter of the bossed part 16b is formed at the opening edge of the light press-fit hole 23 of the boss part 22. 22 has a screw insertion hole 24
A plurality of screw holes 17 of the plate 15 are arranged to face each other and are opened parallel to the axial direction, and one end 8a of the rotary shaft 8 protruding from the case 9 is press-fitted into the plate 15. The plate 15 is inserted into the hole 16 from the chamfered portion 16a side and press-fitted so that its tip protrudes outward in the axial direction from the bossed portion 16b.
is fixed, and the protruding end 8a from the plate 15 at one end protruding from the case 9 of the rotary shaft 8 is inserted into the light press-fit hole 23 of the fan 21 using the resin itself forming the boss portion 22. is press-fitted so that a tight fitting state is created due to the elasticity of The fan 21 and the plate 15 are connected to each other by screws 25.
A fan motor characterized in that the screws are inserted into each of the screw insertion holes 24 and screwed into each of the screw holes 17 to be fastened.