DE102009042452A1 - Cage rotor for electric machines, has rotor made of pierced motor sheet and multiple grooves with arbitrary geometric figure, where end area of grooves pointing to outer circumference of rotor is formed with rare earth material - Google Patents

Abstract

The cage rotor has a rotor (2) made of pierced motor sheet and multiple grooves (3) with arbitrary geometric figure. The end area of the grooves pointing to the outer circumference of the rotor is formed with a rare earth material or a mixture or an alloy of the rare earths. The rare earth material consists of neodymium-iron-boron or a combination close to the material. The free staying end areas of the grooves are filled and subsequently magnetized with lanthanide series-material by a plastic die casting machine in connection to the aluminum die casting head-sided short circuit rings. An independent claim is also included for a method for manufacturing a cage rotor.

Description

The invention relates to the structural design of a squirrel cage rotor for electrical machines, such as motor or generator, in which a certain number of axially disposed rotor grooves is introduced into which a rare earth material and / or a mixture and / or at least in a partial area an alloy of this is introduced, and a method for producing such a rotor.

Electrical machines, which are structurally designed as squirrel cage, are offered in a very diverse design and with a very wide-ranging performance spectrum.

It belongs to the known state of the art that the rotor is formed from a plurality of punched and closely pressed engine plates, which in turn has a certain number of axially disposed rotor grooves. In these grooves, usually as pressed or sintered running, permanent magnets are pressed. In this case, the cross sections of the grooves on a variety of geometric shapes.

With the DE 689 11 929 T2 a squirrel-cage motor is provided with a rotor whose rotor core has a plurality of axial grooves, in which a rotor conductor is arranged, wherein a magnetic bridge for separating the slot opening of the main part of the groove is present.

The grooves are oblique to the rotor axis and the shape of the cross section is a polygon, so that the rotor conductors must have exactly this geometric shape of the groove cross-section.

The disadvantage of this case, however, is that the rotor conductor must always be adapted to the respectively provided groove shape, so that a high outlay for the production and storage is recorded. In this Nutausbildung obliquely to the rotor axis, the introduction of the rotor conductor is additionally difficult.

The present invention is based on the object, a squirrel cage for electrical machines, which is optimized in its structural design, the increased demands on the electromagnetic design and a better speed and performance is justified and to provide a method for producing such a squirrel cage.

According to the invention, this object is achieved in that at least the end of the grooves facing the outer periphery of the grooves is executed filled with a rare earth material, preferably a neodymium-iron-boron combination, wherein according to the inventive method steps the rare earth material following the aluminum Die casting is filled by means of a plastic die casting machine in the grooves and then magnetized or alternatively, the introduction of the Seitenerde material during the aluminum die casting process can be done as a second shot after the introduction of the aluminum.

The main advantages of the invention are to be seen in the fact that the electromagnetic design can be optimized much better by the amounts of added rare earth magnet material.

It is also advantageous that all geometrically possible groove cross-sections can be filled with this rare earth material and also obliquely introduced into the rotor grooves are filled.

Advantageous developments and refinements of the invention can be seen from the remaining dependent claims and from the embodiment described in principle below with reference to the drawings.

Show it

1 FIG. 1: a cross-sectional representation of a stator-rotor pairing of an engine:

2 a cross-sectional view through the rotor with enlarged detail representations A, B, C;

In 1 In principle, a stator-rotor pairing of a squirrel cage motor is shown in cross section.

The stator 1 is made in a known manner from a variety punched soft magnetic sheets and carries the corresponding windings (not shown in the drawing) made of copper for the power supply.

The rotor 2 , also made of a variety of such stamped soft magnetic sheets, has a plurality of, introduced during the stamping process and then compressed sheets formed grooves 3 on, which are formed here in cross-section as an irregular pentagon. In each case, this is the outer circumference of the rotor 2 pointing end portions of the groove 3 formed as a rectangle.

Other cross-sectional shapes of the grooves 3 as well as their end areas are possible. When die casting process are at the head ends of the rotor 2 each a drawing not shown Short-circuit ring applied and the grooves 3 at least partially filled with the aluminum die casting material.

The remaining free from the die casting end portions of the grooves 3 as well as additional, introduced on the front side Sonderuten 5 Now with the rare earth material 4 filled in a corresponding manner.

For example, a neodymium-iron-boron combination is used here, it also being possible for other elements attributable to the group of rare earths and / or mixtures thereof to be used as required.

The filling can be done in such a way that the rare earth material 4 is filled by means of a plastic die casting machine. It is also possible that the introduction of the rare earth material 4 during the aluminum die casting process as a second shot after the introduction of the aluminum.

Following the introduction of the rare earth material 4 takes place, as far as the rare earth material 4 not previously magnetized to the required extent, a corresponding magnetization of the material 4 ,

In 2 the rotor is shown in principle in a cross-sectional view, wherein in the enlarged detail representations A, B and C, the execution of the grooves 3 respectively. 5 should be clarified.

In the detailed representation A is the groove 3 Almost half of the irregular pentagon is filled with aluminum and the end of the rotor facing the outer edge is made of the rare earth material 4 filled.

The detail B shows the example of training a special groove 5 that is directly between two grooves 3 is introduced. And yet this special groove is 5 with the rare earth material 4 filled.

The detailed representation C shows a further development of a special groove 5 that are more inside the rotor 2 is provided and also with the rare earth material 4 is filled.

LIST OF REFERENCE NUMBERS

1

stator

2

rotor

3

groove

4

Rare earth material

5

Sondernut

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 68911929 T2 [0004]

Claims (10)

Squirrel cage rotor for electric machines, in which the rotor consists of stamped engine plates and has a number of grooves of any geometrical shape, characterized in that at least 2 ) facing end portion of the grooves ( 3 ) with a rare earth material ( 4 ) and / or a mixture and / or an alloy of these filled. Electric squirrel cage rotor according to claim 1, characterized in that the rare earth material ( 4 ) consists of neodymium-iron-boron and / or a combination that is close to this material. Electric squirrel cage rotor according to claims 1 and 2, characterized in that the rare earth material ( 4 ) is magnetized. Squirter rotor for electrical machines according to claim 1 to 3, characterized in that the rare earth material ( 4 ) as a powder form in the groove areas ( 3 ) is fillable. Squirter rotor for electrical machines according to claim 1 to 3, characterized in that the rare earth material ( 4 ) as kneadable mass in the Nutbereiche ( 3 ) is fillable. Squirter rotor for electrical machines according to claim 1 to 3, characterized in that the rare earth material ( 4 ) bound in a curable binder in the groove areas ( 3 ) is fillable. Squirrel cage machine for electric machines according to claim 1 and one of claims 2 to 6, characterized in that separate in the rotor ( 2 ) introduced grooves ( 5 ), according to the required magnetic design complete with potting material ( 4 ) are filled. Squirrel cage machine for electric machines according to claim 1 and one of claims 2 to 6, characterized in that separate in the rotor ( 2 ) introduced grooves ( 5 ), according to the required magnetic design only partially with rare earth material ( 4 ) are filled. Manufacturing method for a squirrel cage according to claims 1 to 8, characterized in that following the aluminum die-casting of the head-side short-circuit rings and the at least partial pouring of the grooves 3 with the die-cast material, the remaining free end portions of the grooves ( 3 ) with the rare earth material ( 4 ) are filled by means of a Kunststoffdruckgießmaschine and then magnetized. Method of manufacturing a squirrel cage according to claim 9, characterized in that the introduction of the rare earth material ( 4 ) during the aluminum die casting process of the head-side shorting rings and the at least partial pouring of the grooves 3 takes place with the die casting material as a second shot after the introduction of the aluminum.

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