| 摘要 |
An electric power assisted steering system comprises a motor connected to a portion of a steering mechanism through a worm carried by a worm shaft and a wheel carried by an output shaft operatively coupled to the steering mechanism. The shaft is supported in at least one bearing which has some internal clearances and supports the worm shaft in such a manner that it is free to pivot through an angle in planes which include its own axis due to a degree of axial free play of the first bearing assembly. The bearing assembly comprises an inner race having a groove, an outer race having a groove, and a plurality of ball bearings located between the inner and outer races, and in which the outer race groove is not round when in its position of use such that the ball bearings permit a greater freedom of movement of the inner race relative to the outer race in a first radial direction than in a second radial direction that is orthogonal to the first direction. Tensile or compressive forces may be applied to the bearing assembly to cause the part of the assembly to become not round. |
