DE102010052215A1 - Electric motor e.g. line-start permanent magnet (LSPM) motor has end plate that is adhesively connected at one end face of composite laminated core comprising metal sheets - Google Patents

Abstract

The electric motor has a rotor that includes a composite laminated core (1) comprising metal sheets, on which a short circuit portion is cohesively connected. An end plate (4) is adhesively connected at one end face of the laminated core. The short circuit portion made of aluminum or copper is comprised with short circuit rings (2) closable in axial direction, and short circuit rods (3) connected in rotor axis direction. An independent claim is included for method for manufacturing electric motor.

Description

The invention relates to an electric motor with a rotor and method for producing an electric motor.

It is well known that a rotor of an asynchronous machine has a laminated core arranged on a rotor shaft.

The invention is therefore the object of developing an electric motor with a rotor and method for producing an electric motor, wherein high stator currents are to be allowed. According to the invention, the object is achieved in the electric motor according to the features specified in claim 1.

Important features of the invention in the electric motor with a rotor, that the rotor comprises a composite of single sheet metal plate package to which a short-circuiting cage is integrally connected, in particular is cast, with an end plate is integrally connected to an end face of the laminated core, in particular adhesively bonded.

The advantage here is that the magnets are axially secured. Thus, therefore, high stator currents are allowed, in particular stator short-circuit currents, which make an axially acting force on the permanent magnet.

In an advantageous embodiment, the short-circuit cage has at least two short-circuit rings, which are connected to one another by means of short-circuit bars extending in the axial direction, that is to say the rotor axial direction. The advantage here is that the cage is easy to produce.

In an advantageous embodiment, the laminated core is composed of loose juxtaposed, stanzpaketiert connected and / or welded together single sheet metal parts and is held together by means of the short-circuit cage. The advantage here is that holding together in a simple manner is feasible.

In an advantageous embodiment, permanent magnets are arranged in recesses of the laminated core. The advantage here is that the engine is executable as LSPM engine.

In an advantageous embodiment, the recesses extend in the axial direction and / or are formed continuously. The advantage here is that a simple insertion of the permanent magnets is made possible in the magnetic pockets of the laminated core thus formed.

In an advantageous embodiment, the recesses are cuboid and / or that the permanent magnets formed cuboid. The advantage here is that easily manufacturable permanent magnets are used.

In an advantageous embodiment, the end plates at least partially cover the radial area covered by the permanent magnets and / or recesses. The advantage here is that an axial securing of the magnets can be achieved.

In an advantageous embodiment, the end plate has on its outer circumference radially outstanding tabs, by means of which the end plate is supported on the short-circuit ring of the short-circuit cage, in particular on the inside of the shorting ring of the shorting cage, as long as the temperature of the rotor is less than a critical temperature value,
in particular wherein the tabs act as a centering aid in the integral connection of the end plate with the end face of the laminated core. The advantage here is that the lugs center as a production aid, the end plate before bonding and thus make unbalance avoidable.

In an advantageous embodiment, the tabs in the circumferential direction are regularly spaced from each other. The advantage here is that imbalance or higher moments of imbalance, such as quadrupole moment, are avoidable.

In an advantageous embodiment, the number of tabs on an end plate is an odd number, whereas the number of magnets is even. Alternatively, the reverse, that is, an odd number of magnets and an even number of tabs. The advantage here is that the end plate with the least possible mass is executable.

In an advantageous embodiment, the end plate has a centrally arranged hole whose edge has a radial distance which is smaller than the radial area covered by the permanent magnets or which is at least smaller than the greatest radial distance of the radial area covered by the permanent magnets. The advantage here is that a sufficient assurance can be ensured.

In an advantageous embodiment, the end plate, in particular the tabs of the end plate, spaced from the short-circuit cage, as long as the temperature of the rotor exceeds a critical temperature value. The advantage here is that the tabs have to act only as a production aid-

In an advantageous embodiment, the short-circuit cage has a light metal, such as aluminum or copper, and the end plate is made of steel. The advantage here is that a high conductivity is achievable.

Important features in the method for producing an electric motor are that when inserting the end plate in the ring opening of the shorting ring of the short-circuit cage tabs act as a centering until the adhesive bond between the end plate and the laminated core hardened, in particular so is viable. The advantage here is that in manufacturing prior to the manufacture of the adhesive joint centering is achievable.

Further advantages emerge from the subclaims. The invention is not limited to the combination of features of the claims. For the skilled person, further meaningful combination options of claims and / or individual claim features and / or features of the description and / or figures, in particular from the task and / or posing by comparison with the prior art task.

The invention will now be explained in more detail with reference to figures:
In the 1 is shown an oblique view of the rotor of an electric motor with shorting cage. The electric motor is preferably designed as LSPM engine. The electric motor has a short-circuit cage on the rotor and permanent magnets. Thus, when starting the engine, a predominantly asynchronous mode of operation and upon reaching the setpoint speed a predominantly synchronous mode of operation can be achieved. In particular, a network operation of the engine is thus feasible. An inverter feeding the motor is thus dispensable.

In the 2 is an enlarged section of the 1 shown so that a radially outwardly extending tab 20 the end plate 4 is apparent.

In the 3 is shown a plan view in Rotorwellenachsrichtung, the position of the magnetic pockets 30 Dotted with permanent magnets is indicated in the 4 an axial longitudinal section is shown.

At is a laminated core 1 formed of individual sheet packages, which are preferably stanzpaketiert or held together by means of axially extending weld.

After production of the laminated core, the short-circuit cage is cast. This liquid aluminum is in axially extending recesses in the laminated core 1 injected so that shorting bars 3 arise. In addition, at the axial end portion of the shorting bars 3 a short-circuit ring 2 molded so that this with the shorting bars 3 forms a short circuit cage.

The short-circuit cage holds the laminated core 1 together.

After making the short-circuit cage magnets are in the laminated core 1 axially extending magnetic pockets 30 introduced. For this purpose, four parallelepiped permanent magnets are provided in the circumferential direction regularly spaced arrangement.

For axial securing of the magnets is at both axial end portions of the laminated core 1 one end plate each 4 arranged, the magnetic magnets of the permanent magnets or magnetic bags 30 Covered radial area at least partially covered.

The end plate is after inserting the permanent magnets in the magnetic pockets 30 introduced by ring opening of the shorting ring 2 and with the laminated core, in particular with the first or last single sheet of the laminated core 1 cohesively connected, ie in particular glued to the front side of the laminated core.

The end disc 4 has at its outer periphery radially extending tabs 20 on, with these tabs 20 are spaced apart in the circumferential direction, in particular regularly. The tabs 20 rise in the radial direction over the otherwise circular circumference of the end plate 4 , The survey is at least ten times smaller than the outer diameter of the circular circumference.

By means of the tabs 20 becomes a centering of the respective end plate 4 during insertion and bonding with the laminated core 1 reached. In this case, a much lower temperature is available during production than during operation of the engine. At high, occurring during operation and still permissible temperatures, the short-circuit cage expands in the radial direction further than the end plate 4 , Because the end plate is preferably made of steel, whereas the short-circuit cage is made of a light metal, such as aluminum or copper, or of an alloy containing the light metal. Thus, the tabs lose 20 their contact to the short-circuit ring from a critical temperature.

In a further embodiment of the invention, the number of tabs is an odd number, in particular, this number 5 . 7 or 9 , In contrast, the number of permanent magnets is even, in particular, this number 2 . 4 . 6 or 8th Thus, the end plate radially as narrow as possible and still allows a secure holding the permanent magnets.

In a further embodiment of the invention, the laminated core is formed from loosely arranged one behind the other individual sheets, wherein the compound is formed during spraying of the short-circuit cage.

LIST OF REFERENCE NUMBERS

1

laminated core

2

Shorting ring

3

Shorting bar

4

end disk

20

flap

30

Magnetic bags with permanent magnets

Claims (14)

Electric motor with a rotor, wherein the rotor has a composite of single sheet metal parts laminated core to which a short-circuiting cage is integrally connected, in particular molded, characterized in that an end plate is integrally connected to an end face of the laminated core, in particular adhesively bonded. Electric motor according to at least one of the preceding claims, characterized in that the short-circuit cage has at least two short-circuit rings, which are connected to each other by means of extending in the axial direction, so Rotorachsrichtung, extending short-circuit bars. Electric motor according to at least one of the preceding claims, characterized in that the laminated core of loosely juxtaposed, stanzpaketiert connected and / or welded together single sheet metal parts is assembled and held together by means of the short-circuit cage. Electric motor according to at least one of the preceding claims, characterized in that permanent magnets are arranged in recesses of the laminated core. Electric motor according to at least one of the preceding claims, characterized in that the recesses extend in the axial direction and / or are formed continuously. Electric motor according to at least one of the preceding claims, characterized in that the recesses are cuboid and / or that the permanent magnets are cuboidal. Electric motor according to at least one of the preceding claims, characterized in that the end plates at least partially cover the area covered by the permanent magnet and / or recesses radial region. Electric motor according to at least one of the preceding claims, characterized in that the end disk has radially protruding tabs on its outer circumference, by means of which the end disk is supported on the short-circuit ring of the short-circuit cage, in particular on the inside of the short-circuit cage of the short-circuit cage, as long as the temperature of the rotor is lower than a critical temperature value, in particular wherein the tabs act as a centering aid in the integral connection of the end plate with the end face of the laminated core. Electric motor according to at least one of the preceding claims, characterized in that the tabs in the circumferential direction are regularly spaced from each other. Electric motor according to at least one of the preceding claims, characterized in that the number of tabs on an end plate is an odd number. Electric motor according to at least one of the preceding claims, characterized in that the end plate has a centrally located hole whose edge has a radial distance which is smaller than the radial area covered by the permanent magnet or which is at least smaller than the greatest radial distance of the covered by the permanent magnet radial range. Electric motor according to at least one of the preceding claims, characterized in that the end plate, in particular the tabs of the end plate, is spaced from the short-circuiting cage, as long as the temperature of the rotor exceeds a critical temperature value. Electric motor according to at least one of the preceding claims, characterized in that the short-circuit cage has a light metal, such as aluminum or copper, and the end plate is made of steel. Method for producing an electric motor according to at least one of the preceding claims, characterized in that when inserting the end disk into the ring opening of the Short circuit ring of the short-circuit cage tabs act as a centering until the adhesive bond between the end plate and the laminated core hardened, in particular so is viable, is.

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