JPH03118745A - Self-ventilation cooling type rotary electric machine for vehicle - Google Patents

Abstract

PURPOSE:To reduce the lateral size of a ventilation fan and to decrease a machine body in size by narrowing an interval between the main plate of the fan and a guide plate, and radially arranging many blades over a long length from a suction port on an inner peripheral end side to an outlet on an outer peripheral and side. CONSTITUTION:A main plate 22 protruding from a shaft 8, annular guide plates 23 disposed oppositely, and many blades 24 provided radially are provided. The plates 23 are formed in a wide shape bent substantially in an L shape radially in a longer section than a conventional one. A substantially L-shaped passage obtains ventilation performance equivalent to or more than a conventional one. The lateral size W2 of the outer periphery of a ventilation fan 20 is narrowed as compared with a conventional one by narrowing an interval a2 between the outer peripheral plates 22a and 23a of the plate 22 of the fan 20 and the plate 23 of erected states.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention mainly relates to a self-ventilation-cooled rotating electric machine for a vehicle such as an induction traction motor for a railway vehicle such as an electric train.

(Prior Art) In recent years, progress has been made in the development and practical use of railway vehicles that use an induction traction motor controlled by a VVVF inverter instead of a DC traction motor.

This type of induction traction motor (hereinafter simply referred to as a rotating electric machine) generally has a configuration shown in FIG.

In other words, Figure 5 is a cross-sectional view with the lower half of the rotating electrical machine omitted.
In the figure, reference numeral 1 denotes a cylindrical frame of a rotating electric machine, and a stator core 2 is attached to the inner peripheral surface of this frame 1 by being pressed from both ends with stator core holders 3, and a large number of parts are formed on the inner peripheral surface of this stator core 2. The stator coils 4 are assembled into the slots, and the stator coils 4 are connected to each other by connecting wires 5 to form a stator circuit that generates a rotating magnetic field.

Further, a bearing 7 is attached to the end plate 1a of the stator frame 1 and the mirror cover 6 fitted to the other end, and a shaft (rotor shaft) 8 is rotatably supported by both bearings 7, 7. ing.

A rotor core 9 is attached to this shaft 8 with a rotor core holder 1.
The rotor bar 1 is fixed by pressing from both ends with the rotor core 9, and the rotor bar 1 is inserted into the numerous slots formed on the outer peripheral surface of the rotor core 9.
1 is assembled, and ring-shaped short-circuit rings (end rings) 12 are welded to both ends of the rotor bar 11 to form a cage-shaped rotor.

The rotor rotates when energized, and this rotational force is transmitted from the shaft end of the shaft 8 to the drive gear device via a coupling (not shown) to drive the vehicle.

Such rotating electric machines tend to generate heat and overheat during operation.

Heating above a certain limit accelerates the deterioration of the coil insulator, shortening its lifespan and reducing the strength of the heating element. For this reason, it is necessary to cool the inside of the rotating electric machine (hereinafter simply referred to as the inside of the machine).

As shown in FIG. 4, this cooling method includes forming a cooling air inlet 13 at the upper part of one axial end of the peripheral wall of the frame 1, and also forming a plurality of air exhaust ports 14 at the other axial end of the peripheral wall of the frame 1 in mutually circular circles. A self-ventilation cooling type is generally used in which a fan 15 is fixed to a shaft (rotor shaft) 8 and is formed at intervals in the circumferential direction and is built into the other end of the machine.

In this type of rotating electricity, a fan 15 rotates together with the shaft 8 during operation, and this exhaust action takes cooling air such as outside air into one end of the machine from the cooling air inlet 13, and transfers it to the stator core 2 and the rotor. The gap G between the iron core 9 and
The rotor core 9 is pierced through a plurality of ventilation holes 9a, and the other end side exhaust port 14 is used to exhaust the air to the outside of the machine. This cooling air cools the stator coil 4, rotor bar 11, etc. inside the machine, thereby suppressing temperature rise.

Here, in the above-described self-ventilation cooling rotating electrical machine for a vehicle, the ventilation fan 15 provided inside the machine has a boss portion 16 fitted onto the shaft 8, and a direction from the outer periphery of the boss portion 16 toward the other end in the axial direction. a main plate 17 that protrudes in a trumpet-like expanded state;
An annular guide plate 18 is arranged to face the inner surface of the vertical outer circumferential plate portion 17a of the main plate 17 with a gap therebetween, and these main plates 17
It is composed of a large number of blades 19 sandwiched between an outer circumferential plate portion 17a and a guide plate 18. This ventilation fan has blades 19 arranged radially evenly as shown in Fig. 6 so that there will be no difference in the amount of ventilation into the machine even if the rotational direction of the main motor is reversed depending on the direction of forward or backward movement of the vehicle. It is arranged.

(Problems to be Solved by the Invention) In recent years, there has been an increasing demand for larger capacity, smaller, and lighter rotating electric machines in order to improve vehicle performance and economic efficiency. However, this type of rotating electric machine needs to be stored and installed in a limited narrow space inside the vehicle bogie.
It is important to achieve large capacity without increasing the size. Conversely, it is necessary to make large-capacity rotating electric machines smaller and lighter.

However, in this type of rotating electric machine, the outer diameter of the machine body is determined by the outer diameter of the stator core 2, as shown in Figure 5, and reducing this diameter will result in a decrease in output, so the diameter should be reduced more than the current size. I can't.

On the other hand, the length (axial direction) dimension L1 of the fuselage is the iron core 2 and coil 4.
dimensions determined by motor performance aspects such as the size of the connecting wire 5, the gap S, and the width Wl of the outer periphery of the fan 15.
It is determined by the thickness of the support member. Its size cannot be reduced any further than the present condition due to motor performance, and the gap S cannot be made any smaller than the present condition.

The only remaining objective is to reduce the width W1 of the outer periphery of the ventilation fan 15, which occupies a relatively large amount of space, but if this is simply reduced, the amount of cooling air will be reduced. There is a problem in that the cooling performance inside the aircraft deteriorates, leading to overheating.

The present invention was developed in view of the above circumstances, and it is possible to reduce the width of the outer periphery of the ventilation fan without reducing the amount of cooling air, thereby making it possible to make the aircraft smaller, lighter, or larger in capacity. The purpose of the present invention is to provide a self-ventilation cooling type concave electric rotating machine for vehicles.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention introduces cooling air into the machine from a cooling air inlet at one axial end of the frame by rotating a ventilation fan fixed to a rotating shaft inside the machine. In a self-ventilation cooling rotating electrical machine for a vehicle that circulates this cooling air inside the machine and exhausts it outside the machine from the exhaust port on the other end, the mutual interval between the main plate and the guide plate that face each other with the blades of the ventilation fan in between is determined. At the same time, the guide plate has a wide shape in which the outer circumferential plate part is approximately upright and the inner circumferential plate part is curved in an oval-shaped cross section and extends into the inner circumferential space of the connecting wire of the stator coil to the vicinity of the stator coil. The present invention is characterized in that a large number of vanes are disposed radially between the guide plate and the main plate, extending from the suction port on the inner peripheral end side to the discharge port on the outer peripheral end side.

(Function) In the self-ventilation cooling rotating electric machine for vehicles having the above configuration, by narrowing the mutual distance between the main plate of the ventilation fan and the guide plate,
The width of the outer periphery of the ventilation fan can be reduced, and the longitudinal dimension of the aircraft can be shortened to make it smaller and lighter, or the longitudinal dimension of the aircraft can be kept as it is and the iron core etc. It becomes possible to increase the capacity by increasing the length. Moreover, as mentioned above, by narrowing the mutual distance between the main plate and the guide plate of the ventilation fan, the width of the blades between them becomes narrower. It has a wide shape that is curved in an oval shape in cross section and extends into the inner peripheral space of the connecting wire of the stator coil to the vicinity of the stator coil. By arranging a large number of blades radially over a long distance up to the end discharge port, the length of each blade becomes longer, ensuring sufficient ventilation performance of the ventilation fan, and reducing the amount of cooling air. This makes it possible to maintain sufficient ventilation cooling effects inside the aircraft without causing problems.

(Embodiment) An embodiment of a self-ventilation cooling rotating electrical machine for vehicles according to the present invention will be described below with reference to FIGS. 1 and 2.

Components in the figure that overlap with those shown in FIGS. 5 and 6 are given the same reference numerals to simplify the explanation.

In the figure, reference numeral 20 denotes a cooling ventilation fan that is built into the other end of the machine and fixed to the shaft (rotor shaft) 8, as in the conventional case.
A main plate 22 protruding from the outer periphery toward the other end in the axial direction in an expanded state in a generally trumpet shape, an annular guide plate 23 disposed opposite to the inner surface of the main plate 22 with a gap therebetween, and these main plates 22. It is composed of a large number of blades 24 arranged radially and sandwiched between the guide plate 23 and the guide plate 23.

Here, the ventilation fan 20 has an outer circumferential plate portion 22a of the main plate 22 and an outer circumferential plate portion 2 of the guide plate 23, which face each other with blades 24 in between.
3a is narrowed from the conventional dimension a shown in FIG. 5 to a2 shown in FIG. Now ventilation fan 2
The width dimension of the outer peripheral part of o is shortened from the conventional Wl to W2.

Further, the outer circumferential plate part 23a of this guide plate 23 is in a substantially upright state with a gap S between it and the connecting wire 5 of the stator coil 4, as in the conventional case, and the inner circumferential plate part 23b is curved in an oval shape in cross section so that the connecting wire 5 It extends into the surrounding space to the vicinity of the stator coil 4. As a result, the guide plate 23 has a longer cross-section in the radial direction than the conventional one, and has a wide shape that is curved in an oval shape.

On the outer surface of this guide plate 23, the main plate 22 having a substantially similar cross-sectional shape is arranged. This main plate 22 and guide plate 23
Each blade 24 arranged radially between the main plate 22
The width of the guide plate 23 is narrow in accordance with the mutual spacing between the guide plate 23 and the guide plate 23, but is curved in an abbreviated shape and has a long cross section. It is designed to have a long length extending over a long range II2 up to 26 mm, thereby ensuring ventilation performance equivalent to or higher than that of the conventional type. The length g2 of each blade 24 of the ventilation fan 20 is approximately 2.5 to 4.5 times the width a1 at the outer peripheral end side discharge port 26.

Note that the outer circumferential plate portion 2 of the main plate 22 and the guide plate 23 is in an upright state.
The interval between 2a and 23g (the axial width of the discharge port 26 on the outer circumferential end side) is narrow at a2 as described above, but gradually widens toward the inner circumferential side, and the inner circumferential plate portion 22b is curved in an abbreviated shape.
The axial width of the suction port 25 on the inner peripheral end side is widened to b. Now, as shown in FIG. 2, from the relationship between the inner peripheral end width b' and the outer peripheral end width a' of each blade 24 arranged radially, a
2xa'÷bxb', and the cross-sectional area of the ventilation passage between each blade 24 is approximately equalized from the inner circumferential end side suction port 25 to the outer circumferential end side discharge port 26.

In the self-ventilation cooling rotating electric machine for vehicles having the above configuration, the distance between the outer peripheral plate parts 22a and 23a of the main plate 22 and the guide plate 23 of the ventilation fan 20 in the upright state (the axis of the discharge port 26 on the outer peripheral end side) By narrowing the width (width in the direction of
It can be reduced from W2 to W2, and the longitudinal dimension of the aircraft can be shortened from the conventional Ll to L2-Ll-y by the difference y, resulting in a small size.
It becomes possible to achieve weight reduction. Alternatively, if the longitudinal dimension of the fuselage is left as it is, there will be room in the machine by the above y dimension, so the stator core 2 will be
etc., to increase the capacity.

Moreover, as described above, by narrowing the mutual distance between the main plate 22 and the guide plate 23 of the ventilation fan 20, the blades between them can be
Although the width of the guide plate 23 is narrower, the width of the guide plate 23 is
is approximately upright, and the inner circumferential plate portion 23b is curved in an oval shape in cross section and has a wide shape extending into the inner circumferential space of the connecting wire 5 of the stator coil 4 to the vicinity of the stator coil 4, and the guide plate 23 and Since a large number of blades 24 are arranged radially between the main plate 22 and the long distance from the inner peripheral suction port 25 to the outer peripheral discharge port 26, the length of each blade 24 becomes as long as g2. The ventilation performance of the ventilation fan 22 can be ensured sufficiently, and the ventilation cooling effect inside the machine can be sufficiently maintained without causing a decrease in the amount of cooling air.

That is, FIG. 4 shows the ventilation characteristics due to the difference in the shape of the blades of the ventilation fan.

The type (A fan) in which the ratio of the length g to the width W of the blade is relatively small has a large air volume when the internal resistance is small, but
When the in-flight resistance increases, the air volume decreases sharply. On the other hand, the type (B
It is known that the air volume of a fan (fan) is not so large when the internal resistance is low, but the decrease in air volume is small even when the internal resistance increases.

For this reason, conventionally, the internal resistance was 10 m at 15 m'/min.
A relatively small vehicular DC traction motor of about IIAq (
A fan) is used. On the other hand, the internal resistance is 15
(B fan) is suitable for a large vehicular induction traction motor of about 40 mmAg at m'/min.

Here, in the above-mentioned ventilation fan 20, while the width dimension of the blade 24 is narrowed from the conventional 81 to 82, the length dimension of the blade 24 is increased from g to Ω2. fan) type. Therefore, even though the width dimension of the blades 24 of this ventilation fan 20 is narrower than that of the conventional one, the length dimension is long, so there is no reduction in air volume in a vehicle induction traction motor with a large internal resistance, and it is different from the conventional ventilation fan 15. It will be possible to secure a similar or greater amount of ventilation.

In addition, as described above, in the ventilation fan 20, the cross-sectional area of the ventilation passage between each blade 24 arranged radially is the inner peripheral end side suction port 2.
5 to the outer peripheral end side discharge port 26, the volume of ventilation air is also made uniform, improving the fan ventilation efficiency, and further increasing the volume of air and reducing noise can be expected. It becomes like this.

〔Effect of the invention〕

Since the ventilation-cooled rotating electric machine for vehicles of the present invention is configured as described above, the width of the outer circumference of the ventilation fan can be reduced without causing a decrease in the amount of cooling air, resulting in a compact body.
The effect of making it possible to reduce the weight or increase the capacity can be obtained.

[Brief explanation of drawings]

Fig. 1 is a sectional view of essential parts showing one embodiment of the present invention;
The figure is a front view of a part of the ventilation fan in Figure 1, Figure 3 is a sectional view of the main part showing the possibility of realizing a smaller and lighter aircraft by using the ventilation fan of the same embodiment as above, and Figure 4 is a front view of a part of the ventilation fan in Figure 1. 5 is a sectional view of a conventional example with the lower half omitted, and FIG. 6 is a front view of a portion of the conventional ventilation fan. 1...Frame, 2...Stator core, 4...
Stator coil, 5... Connecting wire, 8... Shaft, 13... Cooling air inlet, 14... Air exhaust port, 20
... Ventilation fan, 22... Main plate, 23... Guide plate, 23a... Outer circumferential plate part, 23b... Inner circumferential plate part, 24
...Blade, 25...Inner circumference end side suction port, 26...Outer circumference end side discharge port.

Claims (1)

[Claims] By rotating a ventilation fan fixed to a rotating shaft inside the machine, cooling air is taken into the machine from the cooling air intake port at one axial end of the frame, circulated inside the machine, and exhausted outside the machine from the exhaust port at the other end. In a self-ventilation cooling rotating electrical machine for a vehicle, the mutual distance between the main plate and the guide plate, which face each other with the blades of the ventilation fan in between, is narrowed, and the guide plate is arranged so that the outer circumferential plate part is substantially upright and the inner circumferential plate part is has a wide shape that is curved in a substantially L-shaped cross section and extends into the inner peripheral space of the connecting wire of the stator coil to the vicinity of the stator coil, and between this guide plate and the main plate there is a A self-ventilation cooling rotating electrical machine for a vehicle, characterized in that a large number of blades are arranged radially over a long period up to the discharge port on the outer peripheral end side.