Patent ID: 7771301

Claim:
A pressure supply between a variator shaft and a pressure chamber for axial displacement of a slidable disc (locating disc) of a pair of conic pulleys of a continuously adjustable automatic transmission, the pressure supply comprising: a longitudinal borehole ( 7 ) and at least two radial shaft boreholes ( 8 , 9 ) located in the variator shaft ( 1 ); at least one radial disc borehole ( 10 ) located in the slidable disc ( 3 ); the at least two radial shaft boreholes ( 8 , 9 ) are separated and axially spaced from one another along an axis of the variator shaft ( 1 ) by an axial distance such that in a first axial position of the slidable disk ( 3 ) both of the at least two radial shaft boreholes ( 8 , 9 ) open to a common annular notch ( 11 ) and in a second axial position of the slidable disc ( 3 ) only one of the at least two radial shaft boreholes ( 8 , 9 ) opens to the common annular notch ( 11 ), the at least two radial shaft boreholes ( 8 , 9 ) being located approximately 90° with respect to one another about a rotational axis of the variator shaft ( 1 ), the annular notch ( 11 ) is located between an inwardly facing surface of the slidable disc ( 3 ) and an exterior surface of the shaft ( 1 ), an axial width of the annular notch is at least as great as a diameter of a first of the at least two radial shaft boreholes ( 8 , 9 ) plus a diameter of a second of the at least two radial shaft boreholes ( 8 , 9 ) plus the axial distance separating the first and the second radial shaft boreholes ( 8 , 9 ) so that the longitudinal borehole ( 7 ), at least one of the first and the second radial shaft boreholes ( 8 , 9 ), the annular notch ( 11 ) and the radial disc borehole ( 10 ) continuously direct an oil flow to the pressure chamber ( 6 ) from the longitudinal borehole ( 7 ) regardless of an axial position and a tangential location of the slidable disc ( 3 ) relative to the variator shaft ( 1 ) so that oil flow is always ensured; and the first axial position is an axial position at which the slidable disc ( 3 ) is incapable of further axial movement in a first direction and the second axial position is, an axial position at which the slidable disc ( 3 ) is incapable of further axial movement in a second direction.