JPH0345149A - Motor - Google Patents

Abstract

PURPOSE:To discriminate the characteristic of completed motor easily by forming plural types of steel board provided with through-holes having different cross-sectional area then making second through-holes having different profile respectively through these steel boards. CONSTITUTION:A rotor 1 is formed by laminating two types of steel boards 2, 3 provided with through-holes 2a, 3a having different cross-sectional area. Then aluminum molten is poured through the through-holes 2a, 3a to form a secondary conductor 5 and the opposite ends of the secondary conductor 5 are coupled through short circuit rings 6, 7. A second through-hole A is made through one steel board 3 at a position close to the shaft 4 so that the through- hole A is not covered by the short circuit ring 6. Since the second through-hole A is provided, position of a steel board having different secondary resistance can be confirmed even when the through-holes 2a, 3a for the secondary conductor are covered by the short ring 6.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an electric motor equipped with a squirrel cage rotor.

[Prior Art] In an electric motor equipped with a squirrel cage rotor, the secondary resistance determined by the secondary conductor of the rotor significantly changes the characteristics.

Conventionally, when changing this secondary resistance, the cross-sectional area of a short-circuit ring formed on the axial end face of the rotor is changed.

However, according to the conventional method, since the secondary conductor is formed by casting aluminum or the like, there is a problem in that the casting mold must be replaced.

Alternatively, the cross-sectional area of the short-circuit ring may be formed from the beginning to be large, and then adjusted by cutting to a size that provides the required characteristics.

However, cutting is a tedious task as it has to be done for each piece, and even if it is mechanized, it is troublesome to switch processes when there are many models with different dimensions.

Other methods include forming secondary conductors using materials with different specific resistances to change the resistance value.

However, in this case as well, it is not easy to melt the materials for the different secondary conductors before casting, and the workability is not good.

Therefore, we considered changing the secondary resistance by combining steel plates with different cross-sectional areas of through-holes for secondary conductors.

However, even in this case, the secondary resistance will be adjusted inside the laminated steel plates, so if the secondary conductor is formed by casting aluminum or other material integrally with the shorting ring, the finished rotor will eventually open. It becomes impossible to tell which one has higher secondary resistance.

Similarly, the ratio of lamination of different steel plates becomes unknown, and the characteristics of the electric motor must be measured to distinguish between them.

The present invention was made in view of these circumstances, and
In order to change the secondary resistance and obtain different characteristics, we focused on the processing of laminated steel plates, which can be manufactured without changing the casting mold or material for the secondary resistance, or without laborious work such as cutting. Moreover, it is an object of the present invention to provide an electric motor configured such that the characteristics of the completed electric motor can be easily distinguished.

[Means for Solving the Problems] The present invention involves forming a plurality of types of steel plates each having through holes for secondary conductors having different cross-sectional areas, and forming second through holes each having a different shape in each of these steel plates. The problem is solved by forming the steel plates, stacking the steel plates so that the through holes for the secondary conductor are aligned, and casting the secondary conductor into the through hole for the secondary conductor.

"Function" When laminating steel plates, the overall volume of the through holes can be set arbitrarily by changing the combination of multiple types of copper plates forming the through holes for the secondary conductor.

Therefore, there is no need to adjust the secondary resistance using a short-circuit ring or material, and electric motors with different characteristics can be obtained without changing the casting mold.

Further, there is no need to cut the short-circuit ring to change the characteristics.

Even if the through hole for the secondary conductor is covered with a short circuit ring, the secondary conductor
The positions of steel plates with different secondary resistances can be confirmed through the through holes.

[Embodiment] The present invention will be described based on an embodiment shown in the drawings. Fig. 1 is a vertical cross-sectional view of a rotor showing essential parts of an electric motor according to an embodiment of the invention, and Fig. The figure is a plan view of the main parts of the steel plates laminated to form the rotor, and Fig. 3 is the main part of the steel plate in which through-holes for secondary resistance are formed, which is different from the steel plate shown in Fig. 2. FIG.

FIG. 4 is a perspective view of essential parts showing the external appearance of a rotor according to another embodiment.

In FIG. 1, the electric motor has a rotor 1 configured to rotate on the inner diameter side of a stator (not shown), and this rotor 1 is formed by laminating two types of steel plates 2 and 3. .

The rotor 1 has a shaft 4 passed through it, and through holes 2a and 3 for secondary conductors formed in each of two types of steel plates 2.3.
A is provided with a secondary conductor 5 formed by casting aluminum.

Further, the secondary conductor 5 is formed by penetrating the steel plates 2.3 in the stacking direction, and furthermore, a plurality of secondary conductors are formed in the circumferential direction, and both ends are connected to short-circuit rings 6.7. connected by.

The shorting rings 6.7 are each formed by casting aluminum integrally with the secondary conductor 5, and although not shown, are formed by placing the rotor 1 in the form of an iron core in a casting mold and pouring molten aluminum into it. It is something.

A second through hole A is formed in one of the two types of steel plates 2.3, and the second through hole A is formed in a portion close to the shaft 4 so as not to be covered by the short circuit ring 6. It is located in

In Figures 2 and 3, the laminated steel plates 2.3 are
The through holes 2a and 3a for the secondary conductor are formed with different cross-sectional areas, respectively, with the through-hole 2a of the steel plate 2 having a large cross-sectional area, and the through-hole 3a of the steel plate 3 having a small cross-sectional area.

A second through hole A is formed in one of the steel plates 3.

In FIG. 4, the rotor 1a is composed of a plurality of laminated steel plates 8a, 8b, and 8C each having a through hole with a different cross-sectional area. Openings 9a and 9b with four widths are formed by opening the outer diameter side of the through hole.
, 9C are formed.

In such a configuration, the electric motor punches out a band-shaped electromagnetic steel plate with a press to form the steel plate 2.3.

And, this kind of press work was done in JP-A-60-961.
This can be easily implemented by continuously punching out electrical steel sheets as described in Japanese Patent No. 52.

In this case, the steel plates 2.3 are punched out and at the same time a predetermined amount is combined to easily obtain only the iron core of the rotor.

Further, the iron core of the rotor 1, which is formed by laminating steel plates 2.3, is placed in a chain mold (not shown), and the through holes 2a, 3a are placed in a chain mold.
A secondary conductor 5 is formed by pouring molten aluminum into the secondary conductor 5.

The formation of such a secondary conductor 5 is carried out by placing an iron core in a mold and then pouring the material that will become the secondary conductor 5 into the through holes 2a and 3a to form a short circuit ring, as described in Japanese Patent Application Laid-open No. 60-9352. 6.7
may be formed integrally.

When forming the secondary conductor 5 in this way, the cross-sectional area of the through holes 2a and 3a formed in the steel plates 2.3 increases during the stacking process of the steel plates 2.3, but the molten aluminum , fluids flow independently and without forming voids,
A secondary conductor 5 and a shorting ring 6.7 can be formed.

The secondary conductor 5 formed in this way has a difference in resistance between the through hole 2a and the through hole 3a, which have different cross-sectional areas, and the secondary conductor 5 has a combined resistance obtained by the amount of the steel plate 2 and the steel plate 3. is determined.

When the secondary resistance is determined in this way, there is no need to adjust the secondary resistance using the shorting ring 6.7, and when manufacturing a motor with improved characteristics, the secondary conductor 5 and the shorting ring 6.7 are connected to #3. !
There is no need to change the type of 1.

The lamination of the steel plates 2.3 may be performed by changing the process of punching to form the through holes 2a and 3a for each predetermined lamination of the steel plates 2.3, or by punching different steel plates 2.3. may be formed individually and stacked.

In any case! ! The through hole 3a with a small 7rWJ product increases the secondary resistance, and the through hole 2a with a large cross-sectional area decreases the secondary resistance, so a combined resistance can be set by connecting the two in series.

Moreover, since the through holes 2a and 3a can be accurately obtained by press work, and the lamination of each of the steel plates 2.3 can be arbitrarily and accurately obtained, the cross-sectional area can be adjusted reliably, and as a result, the secondary resistance can be adjusted accurately.

Then, the completed rotor 1 has two types of steel plates 2.
However, the second through hole A formed in one of the steel plates 3 makes it possible to distinguish between the steel plates where secondary resistance occurs.

Moreover, since this second through hole A is formed only in one steel plate 3, if the depth gauge is inserted in the axial direction,
The amount of lamination of one steel plate 3 can be measured.

Therefore, when the characteristics are adjusted by changing the stacking ratio of the steel plates 2.3, the characteristics can be determined by measuring the second through holes A of the completed rotor 1.

When three or more types of steel plates are combined, the second through holes A may have different diameters or positions.

On the other hand, in another embodiment shown in FIG. 4, the outer diameter side of the through hole for the secondary conductor is opened, and openings 9a, 9b, and 9c are formed with different widths depending on the type of the through hole. Therefore, it is possible to distinguish between rotors with different characteristics just by looking at the outer circumference of the rotor 1a.

Such openings 9a, 9b, 9C are usually 0.8 to 1. o
Since they are on the order of mm, they can be easily distinguished even by a difference of about 0.03 to 0.05 mm.

Therefore, the influence on characteristics such as torque is not large, and the characteristics are not sacrificed.

[Effects of the Invention] According to the present invention, in an electric motor whose characteristics are changed by adjusting the secondary resistance, there is no need to adjust the short circuit ring of the rotor using a casting mold or machining such as cutting. The secondary resistance can be stably obtained, the characteristics can be adjusted extremely stably, and different states of the secondary resistance can be distinguished, and the effects are extremely large industrially.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a rotor showing the main parts of an electric motor according to an embodiment of the present invention, and FIG. 2 is a plan view of the main parts of laminated steel plates constituting the rotor. FIG. 3 is a plan view of a main part of a steel plate forming a through hole, which is different from the steel plate shown in FIG. FIG. 4 is a perspective view of the main parts showing the external appearance of the rotor according to the embodiment of the invention. 1... Rotor, 2.3... Steel plate, 5... Secondary conductor, 6.7... Short circuit ring, 2a, 3a... Through hole,
A...Second through hole.

Claims (2)

[Claims] (1) In an electric motor equipped with a cage-shaped rotor, multiple types of steel plates are formed with through holes for secondary conductors having different cross-sectional areas, and second through holes of different shapes are formed in each of these steel plates. An electric motor characterized in that the rotor is constructed by laminating the steel plates so that the through holes for the secondary conductor are aligned, and casting a secondary conductor into the through hole for the secondary conductor. (2) The outer diameter side of the through-hole for the secondary conductor is open, and the dimensions of this open part are made different from those of the through-hole for the different secondary conductors to form the second through-hole. An electric motor according to claim 1.