Torque transferring device

Claim 1

In a device for transferring a torque between inner and outer members which are axially displaceable in relation to each other through the intermediation of balls operating in juxtaposed, axially extending grooves in the members, the outer member being tubular and enclosing the inner member and having an inner substantially cylindrical surface, the inner member having a substantially cylindrical external surface of a slightly smaller diameter than the internal surface of the outer member to define an annular space therebetween, the improvement that each member is provided with at least three pairs of grooves running in parallel and having a cross section forming part of a circular arc, and where each pair of grooves in the inner member is located to fit in between the grooves at a juxtaposed pair in the outer member in such a manner that the lines defining the cross sections of one groove in the outer member and of one groove in the inner member will form part of a common circle defining a ball runway, said grooves of each pair in the outer member being located at opposite sides of a recess in said outer member and said grooves in the inner member being located at opposite sides of an axial ridge formed within the circular contour of the inner member by means of two axially extending recesses therein, the outer member being provided with axially extending recirculation bores and end passages interconnecting the ends of each recirculation bore with the ends of a corresponding ball runway to permit a continuous recirculation of the balls, the axes of the recirculation bores associated with the runways of each pair being disposed in a plane tangent to the annular space between the members.