Direct drive for a wheel set

1. A drive of a wheel set constructed for support of a chassis and having a wheel set shaft and two wheels mounted to the wheel set shaft, said drive constructed as internal rotor motor for driving the wheel set shaft and comprising a stator; and a rotor formed by a portion of the wheel set shaft and including permanent magnets which are attached to the portion of the wheel set shaft and interact electromagnetically with the stator for propelling the wheel set.

2. The drive of claim 1 , wherein the wheel set shaft is a hollow steel shaft.

3. The drive of claim 1 , wherein the permanent magnets are glued onto the portion of the wheel set shaft.

4. The drive of claim 1 , configured as permanent-excited synchronous motor.

5 .The drive of claim 4 , wherein the synchronous motor is of non-salient pole configuration.

6. The drive of claim 5 , wherein the synchronous motor has a pole number which is greater than or equal to 16.

7. The drive of claim 1 , and further comprising a liquid cooling system for cooling at least the stator.

8. The drive of claim 7 , wherein the stator has a housing of polygonal cross section, thereby defining corners, said liquid cooling system including axial cooling duds formed in the corners of the housing for circulation of a liquid.

9. The drive of claim 1 , and further comprising a two bearings only for support of the wheel set and of the internal rotor motor.

10. The drive of claim 1 , and further comprising at least one central push-pull rod disposed between the wheels of the wheel set.

11. The drive of claim 1 , and further comprising means for at least partially decoupling masses of the drive from the wheel set.

12. The drive of claim 1 , for application in a railway vehicle with a plurality of said wheel set.

13. The drive of claim 12 , wherein the railway vehicle includes a low-floor bogie.

14. The drive of claim 1 , wherein the internal rotor motor has a dimension smaller than a dimension of a side of a wheel of the wheel set.