Patent ID: 8398496
Filing Date: 2013-03-19
Classification: B62D,F16C,F16D

Abstract:
1. A coupling device for an inner shaft and an outer shaft sliding within each other along a direction of a common axis thereof, with balls provided between the inner and outer shafts, each of said balls being provided, on the one hand, in a first concave portion of a first of the inner and outer shafts, and, on the other hand, in a second concave portion of a second of the inner and outer shafts, each of said balls moving along two rolling tracks that cooperate with the first concave portion, each ball moving directly against the second concave portion, the two rolling tracks being pivotable in the first concave portion, and being pushed by an elastic member that bears in the first concave portion, the coupling device comprising: a median plan, in between the two rolling tracks, going through the common axis and a center of said balls; each of the two rolling tracks has: a bearing portion with a bearing side in contact with each of said balls; and a pivot portion with a convex pivot side applying against a concave support side of the first concave portion; the radius of the concave support side is smaller in dimension than the radius of the convex pivot side to define two contact areas between the convex pivot side and the concave support side and a contactless zone between the two contact areas, wherein, for each of the two rolling tracks, the radius of the convex pivot side is progressive.