Slide vane for hydraulic power steering

1. A slide vane ( 20 ) for a hydraulic power steering of automotive vehicles, said slide vane comprising:

a tubular control sleeve ( 24 ) that is connected to an output shaft ( 28 ) and comprises first control grooves ( 32 ) in its inner surface ( 34 );

a tubular sliding sleeve ( 26 ) that is disposed at least in portions within said control sleeve ( 24 ), said sliding sleeve comprises on its outer surface ( 38 ) second control grooves ( 36 ) that may be brought to coincide with the first control grooves ( 32 ) of the control sleeve ( 24 );

said first control grooves ( 32 ) being disposed substantially in the circumferential direction of the tubular control sleeve ( 24 ) and said second control grooves ( 36 ) substantially in the circumferential direction of said tubular sliding sleeve ( 26 ) and the relative position of said control sleeve ( 24 ) and of said sliding sleeve ( 26 ) being relatively variable in the axial direction along a longitudinal axis x-x.

2. The slide vane ( 20 ) as set forth in claim 1 , wherein the sliding sleeve ( 26 ) comprises an inclined groove ( 40 ) into which projects a pressure element ( 42 ) that is fixedly connected to an input shaft ( 22 ).

3. The slide vane ( 20 ) as set forth in claim 2 , wherein the pressure element ( 42 ) is configured to be a pin.

4. The slide vane ( 20 ) as set forth in claim 1 , wherein the sliding sleeve ( 26 ) comprises a longitudinal groove ( 44 ) into which projects a guide element ( 46 ) that is fixedly connected to the control sleeve ( 24 ).

5. The slide vane ( 20 ) as set forth in claim 2 , wherein the inclined groove ( 40 ) is at a gradient angle (a) of about 10° to 45° with respect to the longitudinal axis x-x.

6. The slide vane ( 20 ) as set forth in claim 5 , wherein the gradient angle (α) is 45°.

7. The slide vane ( 20 ) as set forth in claim 1 , wherein the change in the relative position of the control sleeve ( 24 ) and of the sliding sleeve ( 26 ) is effected by a steering torque drive and in one embodiment a pinion drive 50 .

8. The slide vane ( 20 ) as set forth in claim 7 , wherein the steering torque drive is an external motor in the form of a pinion drive 50 that applies a force onto the pressure element ( 42 ).

9. A slide vane ( 20 ) for use in connection with a hydraulic power steering assembly of an automotive vehicle, said slide vane comprising:

a tubular control sleeve ( 24 ) connected to an output shaft ( 28 ) of the power steering assembly, said tubular control sleeve having an inner surface ( 34 ) that defines first control grooves ( 32 ); and

a tubular sliding sleeve ( 26 ) disposed within at least a portion of said control sleeve ( 24 ), said tubular sliding sleeve having an outer surface ( 38 ) that defines second control grooves ( 36 ), said tubular sliding sleeve moveable in an axial direction along a longitudinal axis x-x defined by said slide vane;

wherein said first and second control grooves ( 32 , 36 ) are positioned substantially adjacent to one another such that axial movement of said sliding sleeve ( 26 ) promotes communication between at least one of said first control grooves ( 32 ) and at least one of said second control grooves ( 36 ).

10. A slide vane ( 20 ) as set forth in claim 9 , wherein:

said first control grooves ( 32 ) are positioned in a substantially circumferential direction about said inner surface ( 34 ) of said tubular control sleeve; and

said second control grooves ( 36 ) are positioned in a substantially circumferential direction about said outer surface of said tubular sliding sleeve ( 26 ).

11. A slide vane ( 20 ) as set forth in claim 9 , wherein the position of said control sleeve ( 24 ) and said sliding sleeve ( 26 ) with respect to one another is relatively variable in the axial direction along the longitudinal axis x-x defined by said slide vane.

12. A slide vane ( 20 ) for use in connection with a hydraulic power steering assembly of an automotive vehicle, said slide vane comprising:

a tubular control sleeve ( 24 ) connected to an output shaft ( 28 ) of the power steering assembly, said tubular control sleeve having an inner surface ( 34 ) that defines first control grooves ( 32 ), said first control grooves ( 32 ) positioned circumferentially about said inner surface ( 34 ) of said tubular sleeve; and

a tubular sliding sleeve ( 26 ) disposed within at least a portion of said control sleeve ( 24 ), said tubular sliding sleeve having an outer surface ( 38 ) that defines second control grooves ( 36 ), said second control grooves ( 36 ) positioned circumferentially about said outer surface of said tubular sliding sleeve ( 26 );

wherein said sliding sleeve is moveable in an axial direction along a longitudinal axis x-x defined by said slide vane.

13. A slide vane ( 20 ) as set forth in claim 12 , wherein said first and second control grooves ( 32 , 36 ) are positioned substantially adjacent to one another such that axial movement of said sliding sleeve ( 26 ) promotes communication between at least one of said first control grooves ( 32 ) and at least one of said second control grooves ( 36 ).

14. A slide vane ( 20 ) as set forth in claim 12 , wherein the position of said control sleeve ( 24 ) and said sliding sleeve ( 26 ) with respect to one another is relatively variable in the axial direction along the longitudinal axis x-x defined by said slide vane.