Steering column with rake and telescope adjustment

Abstract

A steering column assembly for a motor vehicle is adjustable in both rake and telescope directions and then locked in a convenient setting by a driver. The locking mechanism for the telescope and rake adjust is motor actuated in response to activation of a toggle switch. The motor can be proximate or remote from the locking mechanism and the steering column assembly. A transmission operates on a rotating cam principal which alternately cycles a clamp of the locking mechanism between locked and unlocked conditions. A drive shaft extends between the motor and the locking mechanism and can be either rigid or flexible. Locking the steering column assembly in an adjusted position can be accomplished either by compressing a capsule bracket against a compression bracket, or via interlocking engagement of pawls with corresponding teeth in respective slots in the capsule and compression brackets.

1 . A steering column assembly for a motor vehicle having an adjustable rake and telescope, said assembly comprising: 
 a column sleeve;    a capsule bracket for fixed mounting relative to the vehicle;    a compression bracket joined to said sleeve and moveably carried upon said capsule bracket for allowing arcuate and axial motion of said sleeve relative to the vehicle;    a locking mechanism having a rotary input and operatively disposed between said capsule bracket and said compression bracket for linear reversing travel between an unlocked condition in which the arcuate and axial position of said sleeve is adjustable and a locked condition in which said sleeve is retained in an adjusted position;    a motor having a rotary output;    a drive shaft rotatably supported between a first end operatively connected to said rotary output of said motor and a second end operatively connected to said rotary input of said locking mechanism for transmitting rotary motion from said motor to said locking mechanism; and    a transmission operatively engaging said rotary input for converting rotary movement in a continuous angular direction into reciprocating linear movement whereby said locking mechanism is actuated from said locked condition to said unlocked condition without reversing the angular direction of said rotary output from said motor.    
     
     
         2 . The assembly of  claim 1 , wherein said second end of said drive shaft is supported for rotation about an axis non-parallel to said linear reversing travel of said lock mechanism.  
     
     
         3 . The assembly of  claim 1 , wherein said first and second ends of said drive shaft are not co-axially aligned.  
     
     
         4 . The assembly of  claim 3 , wherein said drive shaft is flexible.  
     
     
         5 . The assembly of  claim 1 , wherein said first and second ends of said drive shaft are co-axially aligned.  
     
     
         6 . The assembly of  claim 1 , wherein said locking mechanism includes a clamp responsive to reciprocating linear inputs for moving between said locked and unlocked conditions.  
     
     
         7 . The assembly of  claim 6 , wherein said transmission is operatively disposed between said second end of said drive shaft and said clamp.  
     
     
         8 . The assembly of  claim 7 , wherein said locking mechanism includes a cam supported on said second end of said drive shaft.  
     
     
         9 . The assembly of  claim 8 , wherein said locking mechanism includes a cam follower operatively engaging said cam.  
     
     
         10 . The assembly of  claim 9 , wherein said locking mechanism includes a clamp bolt connected at one end thereof to said cam follower and at another end thereof to said clamp.  
     
     
         11 . The assembly as set forth in  claim 7 , wherein said clamp includes a flange in pressing engagement with said capsule bracket when in said locked condition.  
     
     
         12 . The assembly as set forth in  claim 7 , wherein said capsule bracket includes an elongated capsule slot through which said clamp bolt extends.  
     
     
         13 . The assembly as set forth in  claim 12 , wherein said compression bracket includes an elongated compression slot through which said clamp bolt extends.  
     
     
         14 . The assembly as set forth in  claim 13 , wherein said capsule slot includes associated locking teeth.  
     
     
         15 . The assembly as set forth in  claim 14 , wherein said compression slot includes associated locking teeth.  
     
     
         16 . The assembly as set forth in  claim 15 , wherein said clamp includes a capsule pawl adapted for engagement with said teeth of said capsule slot.  
     
     
         17 . The assembly as set forth in  claim 16 , wherein said clamp includes a compression pawl adapted for engagement with said teeth of said compression slot.  
     
     
         18 . A locking assembly for an adjustable rake and telescope steering column, said locking assembly comprising: 
 a rotary input shaft;    a clamp responsive to reciprocating linear inputs for moving between locked and unlocked conditions;    a motor having a rotary output;    a drive shaft rotatably supported between a first end operatively connected to said rotary output of said rotor and a second end operatively connected to said rotary input for transmitting rotary motion therebetween; and    a transmission disposed between said rotary input shaft and said clamp for converting rotary movement in a continuous angular direction from said rotary input shaft into reciprocating linear movement whereby said clamp is actuated from said locked condition to said unlocked condition and back to said locked condition without reversing the angular direction of said rotary output.    
     
     
         19 . A method for adjusting the rake and telescope of a steering column assembly for a motor vehicle, said method comprising the steps of: 
 affixing a compression bracket to the steering column;    supporting the compression bracket upon a capsule bracket to allow arcuate and axial motion of the steering column relative to the vehicle;    shuttling a locking mechanism between an unlocked condition in which the compression bracket is moveable relative to the capsule bracket and a locked condition in which the compression bracket is fixed relative to the capsule bracket and back to the unlocked condition; and    said step of shuttling the locking mechanism including the step of rotating a drive shaft in a non-reversing angular direction.    
     
     
         20 . The method as set forth in  claim 20 , wherein said step of rotating the drive shaft includes rotating about a non-linear axis of rotation.  
     
     
         21 . The method as set forth in  claim 20 , wherein said step of rotating the drive shaft includes rotating about a linear axis of rotation.  
     
     
         22 . The method as set forth in  claim 20 , wherein said step of shuttling the locking mechanism includes the step of placing a clamp bolt in tension.  
     
     
         23 . The method as set forth in  claim 20 , wherein said step of shuttling the locking mechanism includes compressing the capsule bracket into pressing relation against the compression bracket.  
     
     
         24 . The method as set forth in  claim 20 , wherein said step of shuttling the locking mechanism includes moving a pawl into engagement with teeth on the capsule bracket.  
     
     
         25 . The method as set forth in  claim 20 , wherein said step of shuttling the locking mechanism includes rotating a cam against a cam follower.