JPS608535Y2 - self-ventilating electric motor - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a self-ventilating electric motor, and is aimed at easily making it possible to reduce the diameter of the fan in order to reduce fan noise.

FIG. 1 shows a longitudinal cross-sectional view of a conventional self-ventilating electric motor. In the figure, 1 is an end bracket, 2 is a fan,
3 is a yoke, 4 is an exhaust window provided on the yoke 3, and 5 is a field coil.

2 is a partially enlarged view of FIG. 1, and FIG. 3 is a plan view of FIG. 2 viewed from the outside.

In Fig. 1, the cooling air that cools the inside of the electric motor is created by sucking in outside air as shown by the arrow by fan 2.
It passes through the inside of the electric motor and is discharged to the outside from the exhaust window 4.

Next, the configuration around the fan will be explained based on FIG. 2.

The end bracket 1 is fitted onto the inner diameter of the yoke 3 without play, and is fastened with bolts 6 so as not to come off in the axial direction.

The gap A between the outer diameter of the fan 2 and the inner diameter of the yoke 3 and the end bracket 1 should be as small as possible in order to improve the performance of the fan, and is generally about 1.5 TrIIn.

The ventilation windows 4 are provided at several places on the circumference of the yoke 3, and the fan 2
Exhaust the discharged air to the outside.

Also, the field coil 5 is attached to the inner surface of the yoke 3, and the fan 2
and are naturally located on the same diameter.

For example, in the case of rotating electric machines for vehicles, most of them are DC machines, so four field coils 5 are arranged on the circumference in the case of 4 poles, and 6 in the case of 6 poles, and there is a space B between each coil due to the conductor.
The wires are connected using the .

Among these, in the case of vehicle traction motors, the installation location is under the floor of the car body and is attached to a bogie, so there are dimensional restrictions, and there is generally little leeway in the axial dimension, and space B is also severely restricted. It gets narrower.

Therefore, in the above configuration, when fan noise becomes a problem, it is known that reducing the diameter of the fan can reduce the noise level.

According to the experimental results, the reduced sound pressure level is becomes.

For example, if the fan direct current is halved, 6510g1/2=
The sound is reduced by -19.5 dB, or about 20 phons.

FIG. 4 shows a conventional method for realizing a fan with a reduced diameter.

That is, the fan 12 is a fan with a reduced diameter, and in this case, the guide plate 7 protruding inward from the yoke 3 is provided in order to ensure the above-mentioned gap A.

By the way, since this guide plate 7 is constructed integrally with the yoke 3, it becomes a major hindrance to the connection and wiring work of the field coil 5, resulting in poor workability and, in some cases, making this work impossible and reducing the diameter of the fan. There were drawbacks such as not being able to do anything.

This idea was made in order to eliminate the drawbacks of the conventional ones as mentioned above. By attaching a rib to the end bracket and integrally attaching a guide plate to the end of the rib, the fan can be installed without attaching a guide plate to the yoke. The purpose is to provide an end bracket that can reduce the diameter of the end bracket.

An embodiment of this invention will be described below with reference to the drawings.

In Figure 5, 4, 5.12 is the same as in Figure 4,
3 is a yoke from which the guide plate 7 shown in FIG. 4 has been removed, and 11 is an end bracket as shown in FIG. 6 which is attached to the outer end of this yoke 3.

That is, 21 is an end bracket main body similar to the end bracket 1 of FIG. 4, and 22 is a ring-shaped guide plate integrally connected to the inside of this main body 21 via a plurality of ribs 23.

Then, the outer circumferential surfaces C and D of the end bracket main body 21 are fitted to the outer end surface of the yoke 3 in the same manner as in FIG. 4, and the outer diameter E of the ring-shaped guide plate 22 is They are fitted together so that there is no rattling on the circumferential surface, and their inner diameters are configured to maintain a gap A with respect to the fan 12.

Further, an appropriate number of ribs 23 hold the guide plate 22 so as not to block the ventilation window 4.

Since the guide plate 22 is integrated with the end bracket in this way, the connection and wiring of the field coil 5 can be done without the end bracket 11 from the yoke 3, so the work can be done without any problems. There is an advantage that 12 can be adopted.

As described above, according to this invention, since the guide plate of the fan is attached to the end bracket, it has the excellent effect of allowing the use of a fan with a smaller diameter while also making it possible to easily connect and wire the field coil.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a conventional self-ventilating motor, Fig. 2 is a partially enlarged view, Fig. 3 is a partially plan view, and Fig. 4 is a partially sectional view of a conventional small-diameter fan motor. FIG. 5 is a partial sectional view showing an embodiment of this invention, and FIG. 6 is an external view of only the end bracket in this invention. In the figure, 3 is a yoke, 4 is an exhaust window, 5 is a field coil, 11 is an end bracket, 12 is a small diameter fan, 21 is an end bracket body, 22 is a guide plate, and 23 is a rib. Note that the same reference numerals in the drawings indicate the same or equivalent parts.

Claims (2)

[Scope of utility model registration request] (1) A self-ventilating fan attached to the rotor, a yoke with a ventilation window facing the outer periphery of the fan,
In a self-ventilating motor equipped with an end bracket that is detachably attached to the outer end of the yoke, a plurality of ribs are provided inside the end bracket body that is detachably attached to the outer end of the yoke. A ring-shaped guide plate is connected together, and the outer diameter of this guide plate is fitted to the inner peripheral surface inside the exhaust window of the yoke, and the inner diameter is set so as to maintain a predetermined gap for the small-diameter fan. A self-ventilating electric motor characterized by: (2) The self-ventilating electric motor according to claim 1, wherein a plurality of ribs are arranged on the circumference between the end bracket main body and the guide plate.