SQUIRREL-CAGE ROTOR AND METHOD FOR PRODUCING A SQUIRREL-CAGE ROTOR

Abstract

The invention relates to a squirrel-cage rotor (1) having a shaft (2), a rotor plate stack (3) with rotor bars (4) arranged in the interior thereof, and cage rings (5), wherein at least one part of a cage ring (5) is comprised of a disk stack (7), which is constituted as a layered structure of disks (6) with cut-outs (63), through which the ends of the rotor bars (4) project out of the rotor plate stack (3). Adjoining disks (6) in the disk stack (7) are mutually spaced, and form a gap. The clearance between two adjoining disks (6), resulting from the gap, is constituted by moldings (61) which are arranged on the disks (6) wherein, in the gap (8), at least in the region of the moldings (61), a joint connection (9) is provided. The invention further relates to a method for producing a squirrel-cage rotor.

Claims

1. Squirrel-cage rotor (1), specifically for an asynchronous machine, having a shaft (2), a rotor plate stack (3) with rotor bars (4) arranged in the interior thereof, and cage rings (5), wherein at least one part of a cage ring (5) is comprised of a disk stack (7), which is constituted as a layered structure of disks (6) with cut-outs (63), through which the ends of the rotor bars (4) project out of the rotor plate stack (3), characterized in that adjoining disks (6) in the disk stack (7) are mutually spaced, and form a gap (8), the clearance between two adjoining disks (6), resulting from the gap (8), is constituted by moldings (61) which are arranged on the disks (6), and in the gap (8), at least in the region of the moldings (61), a joint connection (9) is provided.

2. Squirrel-cage rotor according to claim 1, characterized in that the joint connection (9) is a soldered connection.

3. Squirrel-cage rotor according to claim 1, characterized in that the moldings (61) are configured to a step-wise design.

4. Squirrel-cage rotor according to claim 1, characterized in that indentations (62) are configured on the reverse side of the moldings (61).

5. Squirrel-cage rotor according to claim 4, characterized in that the indentations (62) are configured to a step-wise design.

6. Squirrel-cage rotor according to claim 4, characterized in that the moldings (61) on one disk (6), in part, engage with the indentations (62) in an adjoining disk (6).

7. Squirrel-cage rotor according to claim 6, characterized in that the moldings (61) on one disk (6) engage with the undercut indentations (62) in an adjoining disk (6).

8. Squirrel-cage rotor according to claim 6, characterized in that the volume of a respective indentation (62) is only partially occupied by a molding (61) which engages with said indentation (62), as a result of which solder from the joint connection (9) fills the residual volume (81) of the indentation (62) which is accessible via the gap (8).

9. Method for producing a squirrel-cage rotor according to claim 1, characterized by the following sequential steps: Provision of a sheet metal blank for a disk (6), Punching of cut-outs (63, 64) for the rotor bars (4) and the shaft (2), Embossing of moldings (61) or indentations (62) in the disk (6), Installation of the disks (6) in a disk stack (7) of a cage ring (5), Arrangement of the cage rings (5) on a rotor disk stack (3), together with rotor bars (4) and a shaft (2), Formation of a joint connection (9) by the introduction of solder into the respective gap (8) configured between adjoining disks (6), at least in the region of the moldings (61).

Description

[0026] Further exemplary embodiments of the invention are described in greater detail with reference to the figures.

[0027] In the figures:

[0028] FIG. 1 shows a schematic longitudinal section of a squirrel-cage rotor,

[0029] FIG. 2 shows a detailed section of FIG. 1, in region A of the cage rings,

[0030] FIG. 3 shows a schematic representation of the process for the punching of cut-outs in a disk, and

[0031] FIG. 4 shows a schematic representation of the process for the embossing of moldings in a disk.

[0032] In all the figures, mutually corresponding parts are identified by the same reference numbers.

[0033] FIG. 1 shows a schematic longitudinal section of a squirrel-cage rotor 1. In this state, the rotor plate stack 3 is positioned on the shaft 2, in combination with two cage rings 5, which enclose the rotor plate stack 3 on the end faces thereof. A plurality of rotor bars 4 are arranged in the interior of the plate stack 3 and the cage rings 5. The bar ends of the rotor bars 4 project into cut-outs 63 in the cage rings 5, and terminate flush to the respective outermost disk 6 in the disk stack 7. As a result of the moldings 61 configured in the disks 6, adjoining disks 6 in the disk stack 7 are mutually spaced.

[0034] In this case, a disk stack 7 is comprised of four disks 6 which, from the shell surface outwards, which constitutes the end face of the respective disks 6, are connected over the outer circumference thereof by means of soldered connections 9. The soldered connections 9 extend radially inwards in the direction of the shaft 2. In the configuration represented, the soldered connections 9, viewed radially, extend fully to the interior, and enclose the moldings 61. In the case represented, as a result of the presence of a given residual gap, the material of the soldered connections 9 also penetrates axially between the cut-outs 63 and the rotor bars 4.

[0035] FIG. 2 shows a detailed section of FIG. 1, in region A of the cage rings. The disk stack 7 of a cage ring 5 is constituted by a plurality of individual disks 6 of equal diameter. Each disk 6 incorporates moldings 61 by means of which, upon the stacking of the disks 6 to form a disk stack 7, a gap 8 is constituted between adjoining disks 6. By way of a joint connection 9, solder is introduced into the respective gap 8. The moldings 61 are formed by a punching process, wherein corresponding indentations 62 are configured on the reverse side of the moldings 61. The moldings 61 and the indentations 62 are configured to a step-wise design, such that they fit together in pairs. In this manner, the moldings 61 on one disk 6, to a certain extent, engage with the indentations 62 in an adjoining disk 6. The volume of a respective indentation 62 is only partially occupied by a molding 61 which engages with said indentation. By this arrangement, solder from the joint connection 9 can penetrate the residual volume 81 of the indentation 62 which is accessible via the gap 8. The cage ring 5 encloses the shaft in an annular manner and, as a compact component, is connected to the rotor bars 4 in a good electrically conductive manner.

[0036] FIG. 3 represents one of the first process steps, whereby cut-outs 63 for the rotor bars and central cut-outs 64 for the shaft are punched out of a sheet metal blank to form a disk 6. The size of the central cut-outs 64 can be selected such that an annular disk 6 is constituted, the diameter of which can also be significantly larger than the shaft diameter.

[0037] FIG. 4 shows a further process step, whereby moldings 61 and indentations 62 are embossed into a disk 6. The embossing tool generates a multi-stepped profile in the indentations 62. The stepping of the indentations 62 is executed such that the latter interlock with the moldings 61 on an adjacently arranged disk 6, upon the connection thereof.

LIST OF REFERENCE SYMBOLS

[0038] 1 Squirrel-cage rotor

[0039] 2 Shaft

[0040] 3 Rotor plate stack

[0041] 4 Rotor bar

[0042] 5 Cage ring

[0043] 6 Disk

[0044] 61 Moldings

[0045] 62 Indentations

[0046] 63 Cut-out for rotor bar

[0047] 64 Central cut-out

[0048] 7 Disk stack

[0049] 8 Gap

[0050] 81 Residual volume

[0051] 9 Joint connection, soldered connection

[0052] A Detailed image section