JPH07147754A - Forcible ventilation cooling type motor - Google Patents

Abstract

PURPOSE:To reduce the length of a cooling air ventilation route significantly by a method wherein a first fan is placed at a position where the fan ventilates toward the part of one side of an axial direction in a motor and a second fan is placed at a position where the fan ventilates toward the part of the other side of the axial direction in the motor. CONSTITUTION:Fans 40 and 41 are attached to the outer circumference of a frame 13 so as to be arranged in an axial direction. The fan 40 is positioned on the side opposite to a linking side and the fan 41 is positioned on the linking side. The air sent by the fans 40 and 41 is introduced into a motor 10 through suction inlets 42 and 43 which are formed in the frame 13. On the other hand, exhaust outlets 44 and 45 are provided in the circumferential direction of the frame 13 at positions approximately opposite to the fans 40 and 41 so as to be arranged in the axial direction. With this constitution, the length of a cooling air ventilation route is significantly reduced and the cooling capability can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forced draft cooling type electric motor in which a cooling mechanism is devised.

[0002]

2. Description of the Related Art Generally, a motor having a low rotation speed, a variable speed motor that is frequently started and stopped, or an electric motor that generates a large amount of heat even at a constant speed operation is insufficient in cooling capacity using a self-cooling fan. Is a forced draft cooling type electric motor.

Here, a conventional forced draft cooling type electric motor will be described with reference to FIG. 3 which is a sectional view when viewed from the front side and FIG. 4 which is a side view. This forced draft cooling type electric motor is
0 is provided with a blower 30, that is, an electric motor with a blower.

In the electric motor 10, the outer frame is constituted by the anti-connection side bracket 11, the connection side bracket 12, and the frame 13 on the peripheral surface which are both end surfaces. Rotating shaft 1
4 is rotatably supported by bearings 15 and 16,
A rotor iron core 17 is provided on the rotating shaft 14. A stator iron core 18 is provided on the inner peripheral surface of the frame 13, an anti-coupling side coil 19a extends from the anti-coupling side end surface of the stator iron core 18, and a coupling side coil 19b extends from the coupling side end surface. . A blow-in port 20 is formed in the upper portion of the frame 13 opposite to the connection side, and an exhaust port 21 is formed in the lower portion of the frame 13 on the connection side.

The blower 30 has a blow-in port 2 of the frame 13.
It is attached in a state of being connected to 0, and blows the air sucked from the suction port 31 into the electric motor 10 through the blow port 20. The blown air flows as shown by the arrows in the figure, and the windings (coils 19a, 19b and rotor coil)
The iron cores 17 and 18 are cooled and exhausted from the exhaust port 21.

The cooling state will be described along the flow of air as a cooling medium. First, the air having a temperature equal to the outside air temperature is sucked from the suction port 31 of the blower 30 and blown out from the blowing port 20. The blown air hits the anti-coupling side coil 19a and the end faces of the iron cores 17 and 18 on the anti-coupling side, and cools the heat from these members. Then the air
The duct around the outer periphery of the stator core 18 and the stator core 1
These members are cooled while moving axially between the rotor 8 and the rotor core 17. Further, the heat from the connecting side coil 19b is dissipated and the heated air is discharged to the outside through the exhaust port 21. The temperature of the cooling air increases as it is sent in the motor 10.

[0007]

By the way, in the above-mentioned conventional electric motor with a blower, since the ventilation passage is long and has many bends, the ventilation resistance becomes large and a relatively high static pressure is required. Further, since the cooling passage is long, the temperature of the air rises and the cooling capacity decreases. It was necessary to increase the air volume to prevent this. For these two reasons, it is necessary to use the blower 30 having a high static pressure and a large amount of air flow, which has the following drawbacks. (1) Noise is loud because a blower with a high static pressure and a large air volume is used. (2) The size of the blower motor is large because the size of the blower is large. (3) The price of the blower is high, and the electric motor with the blower becomes expensive.

In view of the above-mentioned prior art, the present invention provides a forced draft cooling type electric motor which overcomes the drawbacks of (1), (2) and (3) while maintaining a sufficient cooling capacity.

[0009]

SUMMARY OF THE INVENTION According to the structure of the present invention for solving the above-mentioned problems, a frame of an electric motor is provided with first and second fans for feeding external air into the electric motor.
Is arranged at a position for blowing air to one side portion inside the electric motor in the axial direction, and the second fan is arranged at a position for blowing air to the other side portion inside the electric motor in the axial direction. .

[0010]

In the present invention, the first fan cools one side portion of the electric motor and the second fan cools the other side portion of the electric motor. Moreover, the cooling air flows in the radial direction inside the electric motor for cooling.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. It should be noted that parts having the same functions as those of the prior art are designated by the same reference numerals in the following description.

FIG. 1 is a vertical sectional view showing a forced draft cooling type electric motor according to an embodiment of the present invention (a sectional view taken along lines B, C, D and E in FIG. 2), and FIG. 2 is a transverse sectional view showing the embodiment. (A-A in FIG. 1
FIG. As shown in both figures, in the electric motor 10, an outer frame is configured by the brackets 11 and 12 and the frame 13, and a rotor shaft 17 supported by bearings 15 and 16 is provided with a rotor iron core 17. A stator core 18 having coils 19a and 19b is provided on the inner peripheral surface of the frame 13. A fin 13a is formed on the outer peripheral surface of the frame 13.

The two fans 40 and 41 are attached to the outer periphery of the frame 13 in a state of being lined up in the axial direction. The fan 40 is located on the side opposite to the connecting side and the fan 41 is located on the connecting side. Then, the air sent by the fans 40 and 41 enters the electric motor 10 through the blow ports 42 and 43 formed in the frame 13. On the other hand, frame 1
3, exhaust ports 44 and 45 are formed in a line in the axial direction. The exhaust port 44 is located on the opposite side to the exhaust port 45.
Is located on the connection side. Moreover, the exhaust ports 44 and 45 are
It is located substantially opposite to the fans 40 and 41 along the circumferential direction of the frame 13. Further, in the vertical direction (vertical direction), the fans 40 and 41 are located below and the exhaust ports 44 and 45 are located above.

In this embodiment, forced cooling can be performed by operating the fans 40 and 41. That is, the air taken in from the outside by the fan 40 and sent into the motor 10 through the blow-in port 42 flows in the radial direction, mainly hits the anti-coupling side coil 19a and the anti-coupling side portions of the iron cores 17 and 18, and is ejected from these members. The air that has been cooled by the heat is exhausted to the outside through the exhaust port 44. Further, the air taken in from the outside by the fan 41 and sent into the motor 10 through the blow-in port 43 flows in the radial direction and further hits the connecting side coil 19b and the connecting side portions of the iron cores 17 and 18 to generate heat from these members. The air that has been cooled down and becomes hot is discharged to the outside through the exhaust port 45. Further fan 4
Since 0 and 41 are located on the lower side and exhaust ports 44 and 45 are located on the upper side, cooling is performed by adding a cooling effect by natural convection.

Further, the heat of the stator iron core 18 is conducted to the frame 13 from the outer periphery thereof, and the fins 13a of the frame 13 are conducted.
Radiates heat from.

As described above, in the present embodiment, since the opposite connection side and the connection side of the motor 10 are cooled by the separate fans 40 and 41 to send the air in the radial direction, the length of the circulation path of the cooling air is reduced. It is significantly reduced compared to the conventional one, and the flow surface path is less bent and the ventilation resistance is reduced. Therefore, as the fans 40 and 41, even if a fan having a low wind pressure such as a propeller fan is used, sufficient cooling capacity can be obtained.

Since the cost of the fans 40 and 41 is generally low, the cost can be reduced by using the two fans 40 and 41 rather than by using one expensive blower.

[0018]

According to the present invention as described in detail with reference to the above embodiments, two fans are used to send air in the radial direction in the motor to separate the motor from the non-coupling side portion and the coupling side portion. Since the cooling air is cooled by cooling, the length of the circulation path of the cooling air is significantly shortened, the bending of the circulation path is reduced, and the ventilation resistance is reduced. Further, since the temperature rise of the air is small and the cooling capacity is not deteriorated so much, the air volume may be small. Therefore, there are the following advantages. (1) Since there is little ventilation resistance, it is possible to ventilate at a low static pressure, and a small fan with low air pressure can be used, so the overall size of the electric motor and fan is reduced. (2) Since the static pressure is low and the air volume is small, the fan noise is significantly reduced. (3) The price of the two fans used in the present invention is lower than that of the conventional blower. Therefore, the cost can be reduced as a whole.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the present invention.

FIG. 3 is a sectional view showing a conventional forced draft cooling type electric motor.

FIG. 4 is a sectional view showing a conventional forced draft cooling type electric motor.

[Explanation of symbols]

 10 Electric Motors 11, 12 Brackets 13 Frames 14 Rotating Shafts 15, 16 Bearings 17 Rotor Cores 18 Stator Cores 19a, 19b Coils 20 Blow-in Ports 21 Exhaust Ports 30 Blowers 31 Suction Ports 40, 41 Fans 42, 43 Blow-out Ports 44, 45 Exhaust Ports

Claims (1)

[Claims] 1. A frame of an electric motor is provided with first and second fans for feeding external air into the electric motor, and the first fan is arranged at a position for blowing air to one side portion inside the electric motor in the axial direction. The second fan is arranged at a position where air is blown to the other side of the inside of the electric motor in the axial direction, which is a forced draft cooling electric motor.