SHORT-CIRCUIT RING FOR CONNECTING TO CAGE BARS

Abstract

In a method, a short-circuit ring for a squirrel cage of an electric machine is produced through an automated additive production method in one piece with a recess for receiving one end of a cage bar. Material is introduced into a well with a well contour adjacent to the recess on a front axial end of the short-circuit ring through the additive production method, and introduction of the material is repeated into further such wells until all the wells to be filled have been provided with the material, so that the short-circuit ring is connected to the cage bars in an electrically conductive and mechanically robust manner.

Claims

1.-12. (canceled)

13. A method, comprising: producing a short-circuit ring for a squirrel cage of an electric machine through an automated additive production method in one piece with a recess; placing one end of a cage bar in the recess of the short-circuit ring; introducing a material into a well with a well contour adjacent to the recess on a front axial end of the short-circuit ring through the additive production method; and repeating introduction of the material into further such wells until all the wells to be filled have been provided with the material, so that the short-circuit ring is connected to the cage bars in an electrically conductive and mechanically robust manner.

14. The method of claim 13, wherein the additive production method is an additive arc-welding method or a metal powder application method or a 3D metal print method.

15. The method of claim 13, wherein the material is aluminum or copper or alloys thereof.

16. A short-circuit ring for an electric machine, produced by a method as set forth in claim 13.

17. The short-circuit ring of claim 16, comprising a recess for receiving one end of a cage bar from a rear axial end of the short-circuit ring up to an interface, said short-circuit ring comprising a well adjacent to the recess and extending from a front axial end of the short-circuit ring up to the interface and having a well contour which differs in shape and/or size from a recess contour.

18. The short-circuit ring of claim 17, wherein the well contour is circular in shape.

19. The short-circuit ring of claim 17, wherein the well contour corresponds to an enlarged or reduced shape of the recess contour.

20. The short-circuit ring of claim 17, wherein the well contour surrounds at least two of said recess contour.

21. The short-circuit ring of claim 17, wherein the well contour has a length in a radial direction of the short-circuit ring in substantial correspondence to a length of the recess contour in the radial direction of the short-circuit ring, said well being provided adjacent to at least two of said recess.

22. The short-circuit ring of claim 17, further comprising a number of said wells and a number of said recesses, wherein the number of wells corresponds to the number of recesses.

23. A squirrel cage for an electric machine, produced by a method as set forth in claim 13.

24. A squirrel cage for an electric machine, said squirrel cage comprising a short-circuit ring which includes a recess for receiving one end of a cage bar from a rear axial end of the short-circuit ring up to an interface, said short-circuit ring comprising a well extending from a front axial end of the short-circuit ring up to the interface and having a well contour which differs in shape and/or size from a recess contour.

25. The squirrel cage of claim 24, wherein the well contour is circular in shape.

26. The squirrel cage of claim 24, wherein the well contour corresponds to an enlarged or reduced shape of the recess contour.

27. The squirrel cage of claim 24, wherein the well contour surrounds at least two of said recess contour.

28. The squirrel cage of claim 24, wherein the well contour has a length in a radial direction of the short-circuit ring in substantial correspondence to a length of the recess contour in the radial direction of the short-circuit ring, said well being provided adjacent to at least two of said recess.

29. The squirrel cage of claim 24, wherein the short-circuit ring includes a number of said wells and a number of said recesses, wherein the number of wells corresponds to the number of recesses.

30. An electric machine, comprising a squirrel cage as set forth in claim 24.

Description

[0056] The invention is described and explained in more detail below on the basis of the exemplary embodiments shown in the figures, in which:

[0057] FIG. 1 shows a squirrel-cage rotor of an electric machine,

[0058] FIG. 2 shows a section of a well type 3 from FIG. 1,

[0059] FIG. 3 shows a front view of the short-circuit ring,

[0060] FIG. 4 shows a side view of the squirrel-cage rotor, and

[0061] FIG. 5 shows a method for connecting a described short-circuit ring to at least one cage bar, preferably multiple cage bars, in order to produce a squirrel cage.

[0062] FIG. 1 shows a squirrel-cage rotor 10 of an electric machine. The squirrel-cage rotor 10 has a short-circuit ring 1 and cage bars 3, The cage bars are arranged in slots of a laminated core 2. The short-circuit ring 1 has a front axial end 12 and a rear axial end 13. FIG. 1 also shows an interface 11. The short-circuit ring 1 is embodied to receive one end of the cage bar 2 from a rear axial end 13 of the short-circuit ring up to an interface 11, The short-circuit ring has recesses for this purpose. The figure shows various possible types of wells, which are embodied at the front axial end 12 of the short-circuit ring 1.

[0063] The well type 1 is a well in which a well contour 4 corresponds to a recess contour 18.

[0064] In the well type 2, the well contour 5 is greater than the recess contour 18. The figure shows that the well type 2 slopes from the well contour 5 at the front axial end 12 of the short-circuit ring 1 in the axial direction obliquely to the recess contour 18 at the interface 11. The sloping region is indicated with 51.

[0065] The well type 3 also has a well contour 6, which is greater than the recess contour 18.

[0066] The figure shows however that the well type 3 slopes from the well contour 6 at the front axial end 12 of the short-circuit ring 1 in the axial direction directly to the recess contour 18 at the interface 11. This results in a chamfered well. The chamfering is indicated with 61.

[0067] The well type 4 has a circular well contour 7, which surrounds the recess contour 18 of the recess. The well contour 7 has a diameter 71.

[0068] If two wells with the well contour 7 and diameter 71 are disposed next to one another on the short-circuit ring 1, the two wells can interlockas shown in the figureon account of a size of the diameter 71.

[0069] The well type 5 with the well contour 8 surrounds multiple recesses, at least two recesses, and thus multiple recess contours 18. A length 82 in the radial direction 100 of the short-circuit ring 1 of the well contour 8 corresponds in the figure substantially to a length 81 in the radial direction 100 of the short-circuit ring 1 of the recess contour 18.

[0070] The well type 5 is adjacent to at least two recesses, in the figure to four recesses.

[0071] In the figure, the well type 6 with the well contour 9 surrounds two recesses with the recess contour 18. Here, a length 91 in the radial direction 100 of the short-circuit ring 1 of the recesses is less than a length 92 in the radial direction 100 of the short-circuit ring 1 of the well.

[0072] The well type 6 is embodied oval-shaped in the figure. However, other contoursfor example in the shape of circles, triangles, rectangles or polygonsare possible for the wells type 1 to type 6 shown in the figure.

[0073] In the figure, the cage bars 3 extend up to an interface 11. It is however also possible that the cage bars 3 do not extend fully up to the interface 11 or that they protrude further into the short-circuit ring 1 in the direction of the front axial end 12 of the short-circuit ring 1.

[0074] The figure shows various possible wells. Advantageously, only one type is embodied for a short-circuit ring.

[0075] FIG. 2 shows a section of a well type 3 from FIG. 1. FIG. 2 shows an indented region, which results from the fact that the well contour 6 is greater than the recess contour 18.

[0076] FIG. 3 shows a front view of the short-circuit ring 1 with the features from FIG. 1.

[0077] FIG. 4 shows a side view of the squirrel-cage rotor 10. The interface 11 is shown clearly in the figure. The interface 11 is advantageously arranged in relation to an axial length of the short-circuit ring 1, which extends from the front axial end 12 to the rear axial end 13, after 10% to 90% of the axial length of the short-circuit ring 1 viewed from the front axial end 12.

[0078] FIG. 5 shows a method for connecting a described short-circuit ring to at least one cage bar, preferably multiple cage bars, in order to produce a squirrel cage.

[0079] In method step S1, the short-circuit ring and the cage bars are joined. In method step S2, at least one material is introduced into at least one well by means of an additive method. An additive arc-welding method is preferably used as the additive method.

[0080] F? indicates the question whether material has been introduced into all wells to be filled. If this is not the caseindicated with nthe next well is filled by means of the additive method in the method step S2. This is repeated until all wells to be filled have been provided with materialindicated with y. In method step S3, the short-circuit ring is as a result connected to the cage bars in an electrically conductive and mechanically robust manner.