JPH0617794A - Fan mounting device - Google Patents

Abstract

PURPOSE:To provide a mounting device for a fan which facilitates assembly of a fan, an electric motor, and a bearing and improves reliability. CONSTITUTION:A fan mounting device comprises an electric motor shaft 1 provided at an shaft end with a small shaft part 1a and a fan boss 3 in the bore of which fit-in holes 3a and 3b in a two-stage fitted in the electric motor shaft 1 and the small shaft part 1a, respectively, are formed. A fixing screw 4 joined in a screwed-in state with the fan boss 3 is pressed against the small shaft part 1a to mount the fan 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fan mounting device for mounting an air conditioning fan on a drive motor.

[0002]

2. Description of the Related Art In recent years, with the spread of air conditioners, there is a demand for a fan mounting device in which an air conditioning fan can be easily mounted on a driving electric motor to improve productivity and reduce cost. Conventionally, the axis of the electric motor for driving the air conditioning fan is
A straight shaft is used to reduce the man-hours required for shaft processing. For this reason, the bearing was press-fitted from the tip of the shaft.
Then, there is a structure in which the shaft end of the electric motor is milled to provide a D-cut flat surface portion and used as a fixing portion of a screw for fixing the shaft and the fan.

Further, a structure in which a ring-shaped groove is provided as a screw fixing portion for mounting a fan on a shaft of an electric motor, and a rotation stopper and a fan are fixed by tightening a screw is common.

The structure will be described below with reference to FIGS. As shown in the figure, in the former case, the D-cut flat surface portion 12 is provided from the tip of the electric motor shaft 11 by milling, the fixing screw 15 screwed into the fan boss 14 of the fan 13 is tightened, and the tip of the fixing screw 15 is attached to the electric motor. The fan 13 is attached by pressing the D-cut flat surface portion 12 of the shaft 11.

In the latter case, as shown in FIG.
The ring-shaped groove 22 of the motor shaft 21 is provided, and the fixing screw 25 screwed to the fan boss 24 of the fan 23 is tightened,
Attach the tip of the fixing screw 25 to the ring-shaped groove 22 of the motor shaft 21.
The fan 23 is attached by pressing.

[0006]

In such a conventional fan mounting apparatus, in the former case, the fan boss 1 is used.
There is a problem that the fixing screw 15 screwed into the screw 4 and the D-cut flat surface portion 12 of the motor shaft 11 cannot be assembled unless they are aligned with each other.

In the latter case, when the ring-shaped groove 22 is larger than the width W of the bearing 26 that receives the motor shaft 21, when the bearing 26 is press-fitted into the motor shaft 21, the end portion of the motor shaft 21 once. Since the bearing 26 press-fitted into the ring-shaped groove 22 falls into the ring-shaped groove 22 and the inner diameters of the motor shaft 21 and the bearing 26 are misaligned and press-fitted again, there is a problem that the inside of the bearing 26 is damaged and the process is defective. .

Therefore, the width of the ring-shaped groove 22 provided in the motor shaft 21 is made smaller than the width W of the bearing 26 to reduce the bearing failure when the bearing is press-fitted. However, if the width of the ring-shaped groove 22 is reduced, when the fan 23 is attached to the motor shaft 21, the motor shaft 2
There is a problem that it is difficult to align the ring-shaped groove 22 and the fixing screw 25 provided in No. 1 and the number of steps is increased.

Therefore, in order to solve such a problem, as shown in FIG. 4, the diameter φd2 of the electric motor shaft 21a on the tip side of the ring-shaped groove 22a formed in the electric motor shaft 21.
Is smaller than the diameter φD of the electric motor shaft 21 and a clearance is provided between the electric motor shaft 21 and the inner diameter of the fan boss 24 of the fan 23 at the shaft end, the reliability of fan unbalance vibration and drop impact There was a problem with sex.

The present invention solves the above problems, and an object thereof is to provide a highly reliable fan mounting device in which the fan, the motor shaft, and the bearing can be easily assembled.

[0011]

In order to achieve the above object, the fan mounting device of the present invention has an electric motor shaft having a small-diameter shaft portion at its shaft end, and is fitted to the electric motor shaft and the small-diameter shaft portion. A fan boss having a stepped fitting hole formed in the inner diameter is provided, and a fixing screw screwed into the fan boss is pressed against the small diameter shaft portion to attach the fan.

[0012]

According to the present invention, when the bearing is press-fitted, the bearing can be press-fitted into the motor shaft without concern for the small-diameter shaft portion formed at the shaft end of the motor shaft.
When installing the fan, the width of the fixing part of the fixing screw that fixes the fan is not restricted by the width of the bearing, but a part is fixed to the small diameter shaft part formed at the shaft end fitted to the inner diameter of the fan boss. Therefore, it is possible to secure reliability against fan unbalance and drop impact.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. As shown in the figure, the shaft end of the electric motor shaft 1 is formed with a diameter φd1 smaller than the diameter φD of the electric motor shaft 1 to form a small diameter shaft portion 1a, and the electric motor shaft 1 is formed on the inner diameter of the fan boss 3 of the fan 2. A fitting hole 3a into which the motor shaft 1 is fitted and a fitting hole 3b into which the small diameter shaft portion 1a is fitted are formed in two stages so that a part of the shaft end portion of the small diameter shaft portion 1a is fitted. .

The fan boss 3 is provided with a fixing screw 4 whose end is pressed by the small-diameter shaft portion 1a of the electric motor shaft 1 to fix the fan 2 to the electric motor shaft 1.

In the above structure, when the bearing 5 is press-fitted, as shown in FIG. 1 (b), the bearing 5 is not press-fitted to the small diameter shaft portion 1a, but the bearing 5 is simply fitted and inserted into the motor shaft 1. Will be press-fitted from the portion of diameter φD.

When the fan 2 is attached to the electric motor shaft 1, the fitting hole 3a of the fan boss 3 is fitted into the diameter φD portion of the electric motor shaft 1, and the fan is attached to the small-diameter shaft portion 1a of the electric motor shaft 1. When the fitting hole 3b of the boss 3 is fitted to hold the fan boss 3 and the fixing screw 4 is tightened, the tip of the fixing screw 4 is pressed against the small diameter shaft portion 1a, and the fan 2 is attached to the motor shaft 1. Becomes

[0017]

As is apparent from the above embodiments, according to the present invention, a small-diameter shaft portion is formed at the end portion of the electric motor shaft, and the fan boss portion has a two-stage structure fitted to the electric motor shaft and the small-diameter shaft portion. Since the fitting hole is formed, the holding of the fan boss on the motor shaft is stable and the diameter of the shaft end is smaller than the inner diameter of the bearing, so it is possible to reduce bearing defects during motor assembly and improve productivity. A good and reliable fan mounting device can be provided.

[Brief description of drawings]

FIG. 1A is a cross-sectional view of a fan mounting device according to an embodiment of the present invention. FIG. 1B is a cross-sectional view showing a state of the bearing when press-fitted.

FIG. 2 is a cross-sectional view of a conventional fan mounting device.

FIG. 3A is a cross-sectional view of a fan mounting device showing another example of the present invention. FIG. 3B is a cross-sectional view showing a state of the bearing when press-fitted.

FIG. 4 (a) is a cross-sectional view of a fan mounting device showing another example of the same (b) is a cross-sectional view showing a state of the same bearing when press-fitted.

[Explanation of symbols]

 1 Motor shaft 1a Small diameter shaft 2 Fan 3 Fan boss 3a, 3b Fitting hole 4 Fixing screw

Claims (1)

[Claims] 1. An electric motor shaft having a small diameter shaft portion at a shaft end, and a fan boss having an inner diameter formed with two stages of fitting holes for fitting the electric motor shaft and the small diameter shaft portion. A fan mounting device in which a screw is attached to the small-diameter shaft portion to press the screw to mount the fan.