JPS6321180Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cooling device for a rotating electrical machine, particularly a rotating electrical machine used in a machine tool or the like.

Generally, in electric motors, it is desired to seal the stator from the outside air under adverse conditions from the viewpoint of environmental resistance, and it is also necessary to lower the bearing temperature in order to improve the bearing life. Furthermore, with a flange bracket type electric motor, the heat generated by the motor is transferred to the machine to which the motor is attached through the flange bracket and output shaft.Especially when the machine is a machine tool, this heat transfer causes the machine tool to It is thermally deformed and has a negative effect on machining accuracy. Therefore, it is necessary to lower the temperature of the flange bracket and output shaft.

In addition, since the motor is attached to a mating machine, it is essential that the motor be small, lightweight, and low noise.

FIG. 1 shows a side sectional view of a conventional flange bracket type electric motor as an example.

1 is a stator core, 2 is a stator winding coil end, 3 is a frame, 4 is a flange bracket, 5
is the anti-load side bracket, 6 is the bearing, 7 is the shaft, 8 is the rotor core, 9 is the balance disk with fan blade, 10 is the fan blade, 11 is the shroud, 12 is the ventilation hole, 13 is the short circuit ring, 14 is the heat radiation It's Finn.

Conventionally, a balance disk 9 with fan blades was installed on the load side to seal the stator and rotor from the outside air, adjust the rotational balance of the rotor, and cool the flange bracket 4, bearing 6, and shaft 7 by ventilation. It was attached to the shaft 7 between the coil end 2 of the stator winding and the bearing 6.

The load side is sealed from the outside air through a narrow gap between the outer circumferential surface of the balance disk 9 with fan blades and the inner circumferential surface of the stator side cylindrical portion of the flange bracket 4. The flange bracket 4 is located at the outer periphery of the attached balance disk 9 on the fan blade 10 side.
Ventilation holes 12 are provided in the flange bracket 4, and outside air is circulated in the space between the balance disk 9 with fan blades and the flange bracket 4 by the fan ventilation effect caused by the rotation of the balance disk 9 with fan blades.

However, in such a structure, although there is a sealing effect with the outside air, the cooling effect of the flange bracket 4, bearing 6, and shaft 7 is small. In particular, in the case of the flange bracket 4, the speed of the cooling air flowing over the inner surface was slow, and there was no sufficient temperature reduction effect.

○B In order to seal the load side with the outside air through a narrow gap between the outer circumferential surface of the balance disk 9 with fan blades and the inner circumferential surface of the cylindrical part of the flange bracket 4, the balance disk 9 with fan blades is connected to the stator winding. It must be located between the tip of the coil end 2 and the bearing 6. Therefore, the axial length of the electric motor becomes longer by 9 minutes than the balance disk with fan blade, and
The outer diameter of the balance disk 9 with fan blades also had to be made larger than necessary, which was an obstacle to reducing the size and weight.

○C The ventilation hole 12 provided in the cylindrical part of the flange bracket 4 is located on the outer periphery of the fan blade-equipped balance disk 9 on the fan blade 10 side.
The problem is that the ventilation noise caused by the rotation of the fan is directly radiated to the outside from the ventilation hole 12, which increases the noise.

An object of the present invention is to provide a cooling device for a rotating electrical machine that overcomes these drawbacks of conventional devices.

That is, in the present invention, the diameter of the balance disk with fan blade is made smaller than the inner diameter of the stator winding coil end, and it is installed at the inner peripheral position of the coil end.
This is a cooling device for a rotating electric machine configured to perform sealing through a gap by a balance disk and a partition plate with a substantially inverted L-shaped cross section attached to a flange. In addition, this partition plate is made by applying pressure to the inner periphery of a thin donut-shaped flat metal plate and extruding part of the radius, so that the extruded part is cylindrical and does not deform. Since it is formed so as to continue to the flat plate part of the rotating electric machine, for example, if its upper half is shown in cross section, it has a substantially inverted L-shape, and this flat plate-shaped outer peripheral end is the inner peripheral surface of the cylindrical frame that surrounds the inside of the rotating electric machine, or It is fixed to the inner circumferential surface of the cylindrical portion of the bracket that surrounds both end surfaces of the frame, which is joined to the frame, or to the inner circumferential surface of the cylindrical portion of the joint between the frame and the bracket. Moreover, it is also possible to collectively form such a shape using plasticity or the like.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a side sectional view showing the essential parts of an embodiment in which the present invention is applied to a flange bracket type electric motor with a frame.

In each drawing, the same reference numerals represent the same or corresponding parts.

A flange bracket 4 is attached to the load side end surface of the frame 3 to which the stator core 1 wrapped with the stator winding is attached.
The flange bracket 4 rotatably supports a shaft 7 via a bearing 6, and a rotor core 8 having a shorting ring 13 and a heat radiation fin 14 on its end face is attached to the shaft 7.

The flange bracket 4 also has a ventilation hole 12 for communicating the space inside the bearing 6 with outside air.
will be established.

Furthermore, fan blade 10 and shroud 11
Balance disc 9 with fan blade attached
The heat radiation fins 14 of the rotor are made smaller than the inner diameter of the stator winding coil end 2, and the mounting surface of the fan blade 10 is on the bearing 6 side, so that it is located on the inner circumference of the stator winding coil end 2. and the shaft 7 between the bearing 6 and the bearing 6.

On the other hand, one end of a partition plate 15 having a substantially inverted L-shaped cross section is attached to the inner circumference of the frame-side cylindrical portion of the flange bracket 4, and the other end only allows rotation with the outer circumferential surface of the balance disk 9 with fan blades. They are configured to face each other with the smallest diameter interposed therebetween.

Therefore, due to the fan action caused by the rotation of the balance disk 9 with fan blades, outside air cooling air flows in through the ventilation holes 12 and is circulated between the flange bracket 4, the bearing 6, the partition plate 15, and the balance disk 9 with fan blades. While being circulated, it is also ventilated and cooled together with the shaft 7 between the balance disk 9 with fan blades and the bearing 6.

In addition, since the partition plate 15 and the balance disk 9 with fan blades face each other with a minimum width that only allows rotation, air can circulate in the narrow part between the partition plate 15 and the balance disk 9 with fan blades. The stator and rotor can be sufficiently sealed from the outside air.

FIG. 3 is a side sectional view of another embodiment of the present invention.

This is an example of application to a flange bracket type motor with a frameless structure.

In place of the frame 3 to which the stator is attached, a stator attachment ring 16 is installed on the end face of the stator core 1. The difference is that the flange bracket 4 on the load side and the bracket 5 on the anti-load side are fixed to this stator mounting ring 16, and other structures, functions, and effects are the same as in the embodiment shown in FIG.

4 to 7 are side sectional views of essential parts showing modified embodiments of the seal portion and the balance disk 9 portion with fan blade of the present invention.

Figure 4 shows the stepped end surface of the balance disk with fan blade 9, and the stepped end surface and the partition plate 1.
It is sealed by 5.

FIG. 5 shows that a plurality of circumferential grooves 17 each having a depth and groove width of several millimeters are provided on the outer circumferential surface of the balance disk 9 with a fan blade.
A partition plate 15 is provided across the entire width of the partition plate 15 with a thin wall interposed therebetween.

Further, in FIG. 6, circumferential grooves 17 are provided on both sides of the opposing surfaces of the balance disk 9 with fan blade 9 and the partition plate 15.

Regarding the installation of the circumferential grooves 17 shown in Figs. 5 and 6, the principle of labyrinth packing is applied, which applies the fact that when fluid spreads suddenly, pressure decreases and energy is lost. If a widening part is suddenly created in the passage where the fluid is trying to flow, the passage resistance of the fluid will increase and it will become difficult for the fluid to flow.Furthermore, since the circumferential speed due to rotation is high, it will be difficult to flow into the narrow part. This is an application of the effect of becoming.

FIG. 7 shows an example in which there is no heat dissipation fin 14 at the tip of the short-circuit ring 13 of the rotor, and instead of the heat dissipation fin 14, a stirring blade 18 is provided on the end surface of the balance disk 9 with fan blades on the rotor side. It is installed.

FIGS. 8 and 9 show a modified embodiment in which a partition plate 15 is mounted on the outer circumferential side of the balance disk 9 with a fan blade, which is provided opposite to the outer circumferential surface of the balance disk 9 with a thin hole.

FIG. 8 shows the partition plate 15 mounted on the outer peripheral side between the frame 3 and the flange bracket 4. In FIG.

FIG. 9 shows the outer peripheral side of the partition plate 15 mounted on the inner peripheral surface of the frame 3. In FIG.

In this way, the present invention makes the balance disk 9 with fan blades smaller than the inner diameter of the stator winding coil end 2 and positions it on the inner circumferential side of the coil end 2, and also makes the outer circumferential part of the balance disk 9 smaller than the inner diameter of the stator coil end 2. Since this is a cooling device for a rotating electrical machine that is attached to the shaft 7 so as to face the inner circumferential surface of the cylindrical portion of the inverted L-shaped partition plate 15 via a narrow gap, it has the following effects.

○F The axial length between the partition plate 15, which has a substantially inverted L-shaped cross section, and the flange bracket 4 is determined from the axial length between the balance disk 9 with fan blades of the conventional rotating electric machine and the flange bracket 4 in Fig. 1. can also be shortened by the axial length of the balance disk 9 with fan blades, thereby narrowing the outside air ventilation path and increasing the speed of the cooling air, improving the cooling effect of the flange bracket 4 and bearing 6. be able to.

○G As mentioned above, compared to conventional rotating electric machines, the total length of the rotating electric machine can be shortened by the axial length between the balance disk 9 with fan blades and the flange bracket 4, and the outer length of the balance disk 9 with fan blades can be shortened by the axial length between the balance disk 9 with fan blades. Since the diameter can also be made smaller, it is possible to make the rotating electric machine smaller and lighter.

○ Cooling air discharge part of balance disk 9 with fan blade and ventilation hole 12 of flange bracket 4
Since the direction of the discharged cooling air is bent by the partition plate 15, which has a substantially inverted L-shaped cross section, this ventilation noise is reflected, refracted, and radiated to the outside air, making it possible to reduce noise. Become.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a conventional device, Fig. 2 is a side sectional view showing essential parts of one embodiment of the present invention, Fig. 3 is a side sectional view of another embodiment of the present invention, and Figs. FIG. 7 is a side sectional view of the main part of a modified embodiment of the seal part and fan blade part of the present invention, and FIGS. 8 and 9 are side sectional views of the main part of a modified embodiment of the outer periphery attachment of the partition plate. . 1... Stator core, 2... Stator winding coil end, 3... Frame, 4... Flange bracket, 5... Anti-load side bracket, 6... Bearing, 7
... Shaft, 8 ... Rotor core, 9 ... Balance disk with fan blade, 10 ... Fan blade, 11 ... Shroud, 12 ... Ventilation hole,
13...Short-circuit ring, 14...Radiation fin, 15...
Partition plate, 16... Stator mounting ring, 17...
Circumferential groove, 18... Stirring blade.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. Cooling of a rotating electrical machine in which the interior of the rotating electrical machine is partitioned to form a ventilation chamber by a balance disk with fan blades fitted and fixed to a rotating shaft, and ventilation holes are formed in the outer peripheral wall of the ventilation chamber. In the device, the balance disk with blades is disposed on the inner peripheral side of the coil end of the stator winding, and the blade-equipped balance disk is arranged on the stator side side of the ventilation hole in the outer peripheral wall of the ventilation chamber, and the blade has a substantially inverted L-shaped cross section. 1. A cooling device for a rotating electric machine, characterized in that a partition plate is provided, the distal end of the circumferential side facing the outer circumference of the balance disk with fan blades via a narrow gap. 2. A cooling device for a rotating electric machine according to claim 1, wherein a labyrinth groove is formed on at least one of the facing surfaces of the partition plate and the balance disk with fan blades that face each other.