Vehicle steering mechanism

• US 4,785,684 A
• Filed: 09/21/1987
• Issued: 11/22/1988
• Est. Priority Date: 09/30/1986
• Status: Expired due to Fees

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Watanabe, Hiroshi, Nishikawa, Masumi
• Primary Examiner(s): Herrmann, Allan D.
• Application Number:
  US07/098,958
• Time in Patent Office: 428 Days
• Field of Search: 74/89.15, 74/493, 280/775
• US Class Current: 74/493
• CPC Class Codes: B62D 1/181 with power actuated adjustment, e.g. with position memory
• CPC Class Codes: Y10T 74/18656 Carriage surrounded, guided, and primarily supported by member other than screw [e.g., linear guide, etc.]

Abstract

A tiltable and telescopically extensible steering shaft assembly includes a lower main shaft journalled by a stationary bracket and an upper main shaft assembly including a first shaft portion telescopically connected with the lower main shaft through splines and a second shaft portion connected with the first shaft portion for pivotable movements with respect thereto through a universal joint. The stationary bracket carries a first screw shaft and one or more second screw shafts for rotation and engaged with first and second nuts, respectively. An upper bracket is provided on the second shaft portion of the upper shaft assembly and connected with the second nuts for pivotable movements about a transverse tilting axis passing through the pivot point of the universal joint. The first nut is carried by the upper bracket so that a rotation of the first screw shaft produces a tilting movement of the second shaft portion of the upper shaft assembly and rotations of the first and second screw shafts produce a telescopic movement of the upper shaft assembly.

Claims

1. A tiltable and telescopically extensible steering shaft assembly including lower main shaft means, stationary bracket means journalling the lower main shaft means, upper main shaft means having a first shaft portion connected with said lower main shaft means for telescopic movements with respect to the lower main shaft means through spline means and a second shaft portion connected with said first shaft portion for pivotable movements with respect to the first shaft portion through pivot means having a pivot point, first screw shaft means rotatably carried by said stationary bracket means and engaged with first nut means, second screw shaft means rotatably carried by said stationary bracket means and engaged with second nut means, upper bracket means provided on said second shaft portion of the upper shaft means and connected with the second nut means for pivotable movements with respect to the second nut means about a transverse tilting axis passing through the pivot point and extending in a transverse direction, said first nut means being carried on said upper bracket means so that a rotation of the first screw shaft means produces an axial movement of the first nut means causing a tilting movement of the second shaft portion of the upper main shaft means and rotations of the first and second screw shaft means produce axial movements of the first and second nut means causing telescopic movement of the upper main shaft means with respect to the lower main shaft means.

2. A steering shaft assembly in accordance with claim 1 in which driving motor means is provided for driving said first and second screw shaft means.

3. A steering shaft assembly in accordance with claim 1 in which clutch means is provided for transmitting rotation between the first and second screw shaft means, driving motor means for driving said first screw shaft means, means for controlling engagement of the clutch means.

4. A steering shaft assembly in accordance with claim 1 in which said first screw shaft means includes a screw shaft and said second screw shaft means includes a pair of screw shafts.

5. A steering shaft assembly in accordance with claim 4 in which said screw shaft of the first screw shaft means is located beneath the upper shaft means and the screw shafts of the second screw shaft means are located above the upper shaft means.

6. A steering shaft assembly in accordance with claim 3 in which said driving motor means is mounted on the stationary bracket means.

7. A tiltable and telescopically extensible steering shaft assembly including lower main shaft means, stationary bracket means journalling the lower main shaft means, upper main shaft means having a first shaft portion connected with said lower main shaft means for telescopic movements with respect to the lower main shaft means through spline means and a second shaft portion connected with said first shaft portion for pivotable movements with respect to the first shaft portion through pivot means having a pivot point, first screw shaft means rotatably carried by said stationary bracket means and engaged with first nut means, second screw shaft means rotatably carried by said stationary bracket means and engaged with second nut means, upper bracket means provided on said second shaft portion of the upper shaft means and connected with one of the first and second nut means for pivotable movements with respect to said one nut means about a transverse tilting axis passing through the pivot point and extending in a transverse direction, driving means for rotating said first screw shaft means, clutch means provided between said first screw shaft means and said second screw shaft means for transmitting rotation between said first and second screw shaft means, the other of said first and second nut means being carried on said upper bracket means so that an operation of the driving means produces an axial movement of the first nut means causing a tilting movement of the second shaft portion of the upper main shaft means when the clutch means is disengaged and an operation of the driving means produce axial movements of the first and second nut means causing telescopic movement of the upper main shaft means with respect to the lower main shaft means when the clutch means is engaged.