Track-bound vehicle electric machine

Patent metadata

Field	Value
Publication number	US-10855145-B2
Application number	US-201716099365-A
Country	US
Kind code	B2
Filing date	Apr 19, 2017
Priority date	May 11, 2016
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

An electric machine with a rotor ( 4 ) rotatably disposed within a stator ( 1 ) with a stator winding ( 3 ) has a plurality of permanent magnets ( 8 ) received therein. A casing ( 17 ) encloses the stator and the rotor, and an impeller ( 13 ) with blades is fixed to an axle ( 7 ) of the rotor so as to generate a flow of air through the casing for cooling end-turns ( 25 ) of the stator winding by drawing air through an inlet opening ( 18 ) at one end of the casing and blowing it out of the casing through an outlet opening ( 19 ) at the other end of the casing. At least one shutter is arranged to close the outlet opening ( 19 ) when the temperature of the cooling air through the outlet opening reaches a predetermined level well above a maximum level of the temperature possible to be reached under normal operation of the electric machine so as to close the outlet opening upon occurrence of arcing in the end-turns. A temperature dependent member is arranged in the air flow through the outlet opening to obtain such closing.

First claim

The invention claimed is:

1. A track-bound vehicle electric machine configured to act as a motor for creating a traction force of a track-bound vehicle ( 10 ) and comprising:
a stator ( 1 ) having a stator body ( 2 ) with a stator winding ( 3 ) wound therearound and configured to electrically create a plurality of stator poles disposed around the inner periphery of the stator body,
means ( 9 ) configured to connect the stator winding to an AC source or receiver ( 12 ),
a rotor ( 4 ) rotatably disposed within said stator ( 1 ) and having a rotor body ( 5 ) with a plurality of permanent magnets ( 8 ) received therein,
a casing ( 17 ) enclosing the stator and the rotor, and
an impeller ( 13 ) with blades ( 14 ) fixed to an axle ( 7 ) of the rotor at one end ( 15 ) of the stator body to generate a flow of air substantially axially with respect to an axis of rotation ( 6 ) of the rotor towards the other end ( 16 ) of the stator body for cooling end-turns ( 25 ) of the stator winding by drawing air through an inlet opening ( 18 ) at one end of the casing ( 17 ) and blowing it out of the casing through an outlet opening ( 19 , 29 , 39 ) at the other end of the casing,
wherein the machine further comprises at least one shutter ( 20 , 30 , 40 ) arranged in the outlet opening ( 19 , 29 , 39 ) of said casing and an arrangement having a temperature dependent member ( 21 , 31 , 41 ) arranged in the air flow through said outlet opening and configured to hold said at least one shutter in a first open position releasing the outlet opening for flow of cooling air to pass as long as the temperature of said cooling air is below a predetermined level and to cause transfer of said at least one shutter ( 20 , 30 , 40 ) to a second closed position substantially closing said outlet opening ( 19 , 29 , 39 ) of the casing, upon an increase of the temperature of the air flow through said outlet opening above said predetermined level, and
the temperature of said predetermined level is at least 50K above a maximum level of the temperature possible to be reached by said air flow under normal operation of the electric machine.

2. An electric machine according to claim 1 , wherein said at least one shutter ( 20 , 30 , 40 ) is configured to close said outlet opening ( 19 , 29 , 39 ) of the casing completely in said second closed position.

3. An electric machine according to claim 1 , wherein said temperature dependent member ( 21 , 31 , 41 ) is configured to irreversibly transfer said at least one shutter to said second closed position upon an increase of the temperature of the air flow through said outlet opening ( 19 , 29 , 39 ) above said predetermined level.

4. An electric machine according to claim 1 , wherein said predetermined level is 200K-1000K above said maximum level of the temperature possible to be reached by said air flow under normal operation of the electric machine.

5. An electric machine according to claim 1 , wherein said maximum level of the temperature possible to be reached by said air flow under normal operation of the electric machine is 60° C.-130° C., 80° C.-120° C. or approximately 100° C.

6. An electric machine according to claim 1 , wherein said arrangement comprises means ( 23 , 33 ) configured to urge said at least one shutter ( 20 , 30 ) towards said second closed position, and said temperature dependent member ( 21 , 31 ) is configured to prevent said means to move said shutter from said first open position as long as said temperature of said cooling air is below said predetermined level.

7. An electric machine according to claim 1 , wherein said temperature dependent member ( 21 , 31 , 41 ) comprises a bar of a material losing its mechanical strength at a temperature above said predetermined level.

8. An electric machine according to claim 1 , wherein said temperature dependent member comprises a bimetallic strip causing said transfer by temperature dependent prolongation.

9. An electric machine according to claim 1 , wherein said temperature dependent member comprises a portion of a substance reacting chemically upon a temperature thereof reaching said predetermined level and causing transfer of said at least one shutter ( 20 , 30 , 40 ) to said second closed position.

10. An electric machine according to claim 9 , wherein said substance is an explosive material or a substance rapidly increasing its volume when reaching a temperature of said predetermined level.

11. An electric machine according to claim 9 , wherein said substance ( 51 ) is configured to, when reaching a temperature of said predetermined level operating said at least one shutter ( 50 ) from a distance by mechanical means ( 53 ), such as a rod or wire, or pressure or flow through a pipe.

12. An electric machine according to claim 1 , comprising a plurality of said shutters ( 30 , 40 ) configured to together close said outlet opening ( 29 , 39 ) of the casing in said second closed position.

13. An electric machine according to claim 1 , including shutters which are interconnected by a member ( 44 ), such as a rod, and said temperature dependent member ( 41 ) is configured to cause this interconnecting member to transfer all of these shutters into said second position upon an increase of the temperature of the air flow through said outlet opening above said predetermined level.

14. A driving arrangement for a track-bound vehicle, comprising an electric machine according to claim 1 .

15. A method for generating a traction force of a track-bound vehicle ( 10 ), comprising using an electric machine according to claim 1 .

16. A track-bound vehicle having a driving arrangement for generating a traction force of the vehicle including at least one electric machine according to claim 1 .

17. A track-bound vehicle according to claim 16 , wherein said at least one electric machine is secured to a chassis of the vehicle ( 10 ), or secured to the bogie of the vehicle, or mounted on the axle, or a combination thereof, with said outlet opening ( 19 , 29 , 39 ) of the casing directed downward to be directed towards a rail track when the vehicle is standing on the rail track.

18. An electric machine according to claim 1 , wherein said second closed position closes said outlet opening ( 19 , 29 , 39 ) of the casing by at least 80%.

19. An electric machine according to claim 18 , wherein said second closed position closes said outlet opening ( 19 , 29 , 39 ) of the casing by at least 90%.

20. An electric machine according to claim 2 , wherein said temperature dependent member ( 21 , 31 , 41 ) is configured to irreversibly transfer said at least one shutter to said second closed position upon an increase of the temperature of the air flow through said outlet opening ( 19 , 29 , 39 ) above said predetermined level.

Assignees

• Bombardier Transp Gmbh

Inventors

• Andersson Svante

Classifications

• H02K5/207 Primary

  with openings in the casing specially adapted for ambient air · CPC title

• H02K2213/09

  Machines characterised by the presence of elements which are subject to variation, e.g. adjustable bearings, reconfigurable windings, variable pitch ventilators · CPC title

• H02K7/006

  Structural association of a motor or generator with the drive train of a motor vehicle · CPC title

• H02K9/06

  with fans or impellers driven by the machine shaft · CPC title

• H02K2205/09

  Machines characterised by drain passages or by venting, breathing or pressure compensating means · CPC title