Labyrinth seal for three-phase machines

Patent metadata

Field	Value
Publication number	US-10103597-B2
Application number	US-201415031192-A
Country	US
Kind code	B2
Filing date	Oct 17, 2014
Priority date	Oct 22, 2013
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

The present invention relates to electrical machines having a shaft rotatably supported in a housing and having a labyrinth seal with labyrinth contours engaging into one another for sealing the housing with respect to the shaft. The invention in this respect in particular relates to the labyrinth seal for sealing the housing of a three-phase machine with respect to a shaft rotatable relative to the housing. In accordance with the invention, at least one side of the labyrinth seal is at least provided with an insulating coating in the region of the labyrinth contours.

First claim

The invention claimed is:

1. An electric machine having a shaft rotatably supported in a housing and having a labyrinth seal with labyrinth contours which engage into one another for sealing the housing with respect to the shaft, wherein at least one side of the labyrinth seal is at least provided with an insulating coating in a region of the labyrinth contours, wherein the shaft is supported at the housing by at least one hybrid roller bearing comprising roller bodies and races, the roller bodies formed from a material different than a material of the races, and wherein the roller bodies are formed from an electrically non-conductive material, the labyrinth seal having an insulating coating provided at both sides of said hybrid roller bearing.

2. The electric machine in accordance with claim 1 , wherein both mutually oppositely disposed sides of the labyrinth seal are at least provided with one insulating coating in the region of the labyrinth contours.

3. The electric machine in accordance with claim 1 , wherein at least one of two labyrinth seal parts has one of the labyrinth contours completely produced from insulating material.

4. The electric machine in accordance with claim 1 , wherein the hybrid roller bearing has ceramic roller bodies and steel races.

5. The electric machine in accordance with claim 1 , wherein it is configured as a three-phase machine whose shaft is galvanically separated with respect to the housing by insulated bearings.

6. A labyrinth seal for sealing a housing of a three-phase machine with respect to a shaft rotatable with respect to the housing having at least two seal parts which have labyrinth contours which engage into one another, wherein at least one side of the labyrinth seal is at least provided with an insulating layer in a region of the labyrinth contours in a form of a ring-shaped disk,
wherein the shaft is supported at the housing by at least one hybrid roller bearing comprising roller bodies and races, the roller bodies formed from a material different than a material of the races, and
wherein the roller bodies are formed from an electrically non-conductive material, the insulating layer of the labyrinth seal provided at both sides of said hybrid roller bearing.

7. The labyrinth seal in accordance with claim 6 , wherein both sides of the labyrinth seal are provided with a respective insulating coating.

8. The labyrinth seal in accordance with claim 6 , wherein at least one of the labyrinth seal parts which has one of the labyrinth contours is completely produced from insulating material.

9. The electric machine in accordance with claim 3 , wherein the insulating material is plastic.

10. The electric machine in accordance with claim 4 , wherein the ceramic roller bodies are roller balls.

11. The electric machine in accordance with claim 5 , wherein the three-phase machine is a synchronous generator.

12. The labyrinth seal in accordance with claim 8 , wherein the insulating material is plastic.

13. A system, comprising:
an electric machine having a shaft rotatably supported in a housing and having a labyrinth seal with labyrinth contours which engage into one another for sealing the housing with respect to the shaft, wherein at least one side of the labyrinth seal is an insulating layer in a form of a ring-shaped disk at the labyrinth contours, the insulating layer forming an external surface of the electric machine,
wherein the shaft is supported at the housing by at least one hybrid roller bearing comprising roller bodies and races, the roller bodies formed from a material different than a material of the races,
wherein the roller bodies are formed from an electrically non-conductive material, the insulating layer of the labyrinth seal provided at both sides of said hybrid roller bearing.

Assignees

• Liebherr Components Biberach Gmbh

Inventors

• Graner Klaus
• Lis Johann
• Mendes Marijo

Classifications

• F16C33/303

  of hybrid bearings, e.g. rolling bearings with steel races and ceramic rolling elements · CPC title

• H02K5/1732

  radially supporting the rotary shaft at both ends of the rotor (H02K5/1737 takes precedence) · CPC title

• F16J15/453

  characterised by the use of particular materials {(F16J15/444 takes precedence)} · CPC title

• F16C2380/26

  Dynamo-electric machines or combinations therewith, e.g. electro-motors and generators · CPC title

• F16C2204/60

  Ferrous alloys, e.g. steel alloys · CPC title