Abstract:
The invention provides a steering column for a vehicle. The steering column includes a steering column jacket defining a column axis. The steering column jacket is operable to at least partially encircle a steering shaft in a vehicle. The steering column also includes a tilt housing engaged with the steering column jacket for tilting movement about a tilt axis between a plurality of tilt positions. The steering column also includes a locking member supported for linear movement by the tilt housing. The locking member has a tip moveable outwardly with respect to the column axis to a locked position contacting the steering column jacket and inwardly towards the column axis to an unlocked position spaced from the steering column jacket.

Description:
This invention claims priority to U.S. Provisional Application No. 60/527,932, filed Dec. 8, 2003. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a steering column for a vehicle and, more specifically, relates to a control mechanism for selectively tilting a tilt housing in a steering column assembly relative to an inner column jacket. 
     BACKGROUND OF THE INVENTION 
     It can be desirable to tilt a steering wheel in a motor vehicle to accommodate different operators of the motor vehicle. Specifically, the position of the steering wheel relative to the steering column can be changed to enhance the operator&#39;s comfort and the operator&#39;s control of the vehicle. The steering column can support a steering wheel with a tilt housing that is rotatable relative to another component of the steering column, such as an inner column jacket. However, current mechanisms for controlling the position of the steering wheel relative to the steering column are not as efficient as desired. 
     SUMMARY OF THE INVENTION AND ADVANTAGES 
     The invention provides a steering column for a vehicle. The steering column includes a steering column jacket defining a column axis. The steering column jacket is operable to at least partially encircle a steering shaft in a vehicle. The steering column also includes a tilt housing engaged with the steering column jacket for tilting movement about a tilt axis between a plurality of tilt positions. The steering column also includes a locking member supported for linear movement by the tilt housing. The locking member has a tip moveable outwardly with respect to the column axis to a locked position contacting the steering column jacket and inwardly towards the column axis to an unlocked position spaced from the steering column jacket. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: 
         FIG. 1  is a perspective view showing a right-hand side of a tilt housing rotatably associated with an inner column jacket; 
         FIG. 2  is a perspective view showing a front side of the tilt housing and the inner column jacket shown in  FIG. 1  and also shows a tilt control lever assembly in the locked position according to the exemplary embodiment of the present invention; 
         FIG. 3  is a perspective view showing a lower, left-hand side of the exemplary embodiment of the invention shown in  FIGS. 1 and 2 ; 
         FIG. 4  is a perspective view showing the right-hand side of a partial cross-section of the tilt housing, the inner column jacket, and the tilt control lever assembly in the locked position; 
         FIG. 5  is a partial cross-sectional, detailed view of the tilt control lever assembly shown in  FIGS. 2-4 ; 
         FIG. 6  is a perspective view showing the right-hand side of a partial cross-section of the tilt housing, the inner column jacket, and the tilt control lever assembly in the unlocked position; 
         FIG. 7  is a left-hand perspective view of the structure shown in  FIG. 6 ; 
         FIG. 8  is a bottom view of the tilt control lever assembly in locked and unlocked positions; 
         FIG. 9  is a left-hand side view of the exemplary embodiment of the invention wherein the tilt control lever assembly is in an unlocked position; 
         FIG. 10  is a bottom view corresponding to the side view in  FIG. 9 ; 
         FIG. 11  is a front view corresponding to the views in  FIGS. 9 and 10 ; 
         FIG. 12  is a partial cross-sectional view taken along the sectional line in  FIG. 11 ; 
         FIG. 13  is a left-hand side view of the exemplary embodiment of the invention wherein the tilt control lever assembly is in a locked position; 
         FIG. 14  is a bottom view corresponding to the side view in  FIG. 13 ; 
         FIG. 15  is a front view corresponding to the views in  FIGS. 13 and 14 ; 
         FIG. 16  is a partial cross-sectional view taken along the sectional line in  FIG. 15 ; 
         FIG. 17  is a perspective view of a locking according to the exemplary embodiment of the invention; 
         FIG. 18  is a perspective view of a tilt lever according to the exemplary embodiment of the invention; 
         FIG. 19  is a perspective view of a first spring according to the exemplary embodiment of the invention; 
         FIG. 20  is a perspective view of a second spring according to the exemplary embodiment of the invention; 
         FIG. 21  is a perspective view of a retaining ring according to the exemplary embodiment of the invention; 
         FIG. 22  is a perspective view of the inner column jacket according to the exemplary embodiment of the invention; 
         FIG. 23  is a first perspective view of the tilt housing according to the exemplary embodiment of the invention; and 
         FIG. 24  is a second perspective view of the tilt housing according to the exemplary embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to  FIGS. 1 and 2 , a tilt and telescope steering column assembly  10  includes an outer column jacket  12  and an inner column jacket  14 . The inner column jacket  14  is slidably received by the outer column jacket  12  and is selectively movable with respect to the outer column jacket  12  to provide telescopic adjustment of the inner column jacket  14  relative to the outer column jacket  12 . A tilt housing  16  is rotatably associated with the inner column jacket  14 . According to a particular feature of the invention, the tilt housing  16  is selectively tiltable relative to the inner column jacket  14 . Tilting adjustments of the tilt housing  16  relative to the inner column jacket  14  are controlled by a tilt control lever assembly  18 . 
     Referring now to  FIGS. 1 and 22 , the inner column jacket  14  includes a body portion  20  and a receiving portion  22 . The body portion  20  is received by a correspondingly shaped aperture defined by the outer column jacket  12  for sliding movement relative to the outer column jacket  12 . The receiving portion  22  is not received in the aperture defined by the outer column jacket  12  in the exemplary embodiment of the invention. The receiving portion  22  is rotatably connected to the tilt housing  16  and defines a cavity  24  for receiving at least a portion of the tilt housing  16  and a pair of aligned apertures  26 ,  28  for defining an axis of rotation between the tilt housing  16  and the receiving portion  22 . 
     Referring now to FIGS.  1  and  22 - 24 , the tilt housing  16  includes a face plate  30  and defines a shaft aperture  32 . When the steering column  10  is assembled to a vehicle, a steering shaft  34  for connection to a steering wheel extends through the shaft aperture  32 . The tilt housing  16  also includes first and second yokes  36 ,  42 . The first yoke  36  includes projections  38  and  40 . The second yoke  42  includes projections  44  and  46 . The projections  38 ,  40 ,  44 ,  46  define apertures  48 ,  50 ,  52 ,  54 , respectively. When the tilt housing  16  is rotatably assembled with respect to the inner column jacket  14 , the apertures  48 ,  50 ,  52 ,  54  are coaxially aligned with the apertures  26 ,  28  shown in  FIG. 22 . A pin  56 , shown in  FIG. 1 , is inserted in the apertures  52 ,  28  and  54  when the tilt housing  16  is rotatably assembled to the inner column jacket  14 . Likewise, a pin  58 , shown in  FIG. 9 , is inserted in the apertures  48 ,  26  and  50  when the tilt housing  16  is rotatably assembled to the inner column jacket  14 . When the tilt housing  16  is rotatably associated with the inner column jacket  14 , a sidewall  60  if the inner column jacket  14  is disposed between the projections  38 ,  40  of the first yoke  36 . Similarly, a sidewall  62  of the inner column jacket  14  is disposed between the projections  44 ,  46  of the second yoke  42 . 
     Referring now to  FIG. 1 , the tilt housing  16  is rotatable with respect to the inner column jacket  14  about an axis of rotation defined by the pins  56 ,  58 . The tilt housing  16  is rotatable between first and second end limits of travel. Several angular stop positions or tilt settings, can be defined along the path of rotational movement of the tilt housing  16  relative to the inner column jacket  14 . A first end limit of travel is defined when an engaging surface  64 , defined by the projection  44 , contacts and engages an engaging surface  66  defined by a transverse projection  68  extending from the sidewall  62 . The second end limit of travel is defined when a second engaging surface  70 , defined by the tilt housing  16 , engages a second engaging surface  72  defined by the transverse projection  68 . 
     Referring now to  FIGS. 1 and 19 , the assembly  10  includes a first spring  74  positioned between the tilt housing  16  and the inner column jacket  14 . The spring  74  urges the tilt housing  16  toward the first end limit of travel. When the steering column assembly  10  is assembled to a vehicle, the first spring  74  will or urge the steering wheel upwardly. 
     The spring  74  can be a variable rate spring to enhance the operation of the steering column assembly  10 . For example, it may be desirable to urge the tilt housing  16  toward the first end limit of travel at a constant rate along the rotational path of movement of the tilt housing. A constant rate spring would exert an increasing amount of force in response to an increasing amount of compression. 
     Referring now to FIGS.  19  and  22 - 24 , a first end  76  of the spring  74  can be received in a blind receiving aperture  78  defined by the transverse projection  68 . A second end  80  of the spring  74  can be received in a blind receiving aperture  82  defined by the tilt housing  16 , adjacent the second yoke  42 . 
     Referring now to  FIGS. 4 and 6 , the assembly  10  includes the tilt control lever assembly  18  to selectively control rotational movement between the tilt housing  16  and the inner column jacket  14 . The assembly  18  includes a locking member or pin  84  and a lever  86  for moving the pin  84  between a locked position and an unlocked position. The pin  84  moves linearly and passes through a transverse aperture  88  defined by the tilt housing  16 . The pin  84  is selectively insertable in a slot  90  defined by the inner column jacket  14 . When the pin  84  is inserted in the slot  90 , the tilt housing  16  and the inner column jacket  14  are locked with respect to one another, best shown in  FIGS. 2 ,  4  and  16 . When the pin  84  is removed from the slot  90 , the tilt housing  16  and the inner column jacket  14  are unlocked with respect to one another, best shown in  FIGS. 6 ,  7  and  12 , and the tilt housing  16  can rotate relative to the inner column jacket  14 . 
     Referring now to  FIGS. 1 and 6 , the slot  90  extends along an arcuate path corresponding to the rotational path of movement of the tilt housing  16  relative to the inner column jacket  14 . The aperture  88  is aligned with and communicates with the slot  90  throughout the movement of the tilt housing  16  between the first and second end limits of travel. The slot  90  defines corresponding step surfaces  92 ,  94 , resulting in the slot  90  having wider and narrower portions. The individual steps of the step surfaces  92 ,  94  define angular stop positions or tilt settings along the rotational path of movement of the tilt housing  16 , the wide portions being tilt positions and the narrower portions separating tilt positions. A tip  96  of the pin  84  is shaped to correspond to the shape of the individual steps of the step surfaces of  92 ,  94 . In the exemplary embodiment of the invention, the tip  96  is rectangularly shaped and the individual steps of the step surfaces  92 ,  94  defined rectangular openings. 
     Referring now to  FIGS. 5 ,  7  and  8 , the pin  84  is moved between the locked position and the unlocked position by the lever  86 . The pin  84  includes a cam follower portion  98  and the lever includes a cam portion  100 . In the exemplary embodiment of the invention, the cam follower portion  98  includes a slot  102  and the cam portion  100  includes a pin  104 . The pin  104  pierces the slot  102  and moves the cam follower portion  98  in response to rotation of the lever  86 . 
     As best seen in  FIG. 8 , the lever  86  is rotatable between a locked position designated at  106  and an unlocked position designated at  108 . When the lever  86  is at the locked position  106 , the tip  96  is positioned in the slot  90 . When the lever  86  is at the unlocked position  108 , the tip  96  is retracted from the slot  90 . A retaining ring  110  can be affixed to a distal end of the pin  104  to prevent the pin  104  from moving out of the slot  102 . 
     Referring now to  FIGS. 8 ,  18  and  23 , the lever  86  is rotatably associated with the tilt housing  16  to rotate between the locked position  106  and the unlocked position  108 . The lever  86  includes a pin  112  insertable in an aperture  114  defined by the tilt housing  16 . As best shown in  FIGS. 5 and 20 , the assembly  10  also includes a second spring  116  disposed in slot  102  to bias the lever  86  to the locked position  106 . 
     In operation, an operator of the vehicle can grasp a gripping portion  118 , as shown in  FIG. 8 , of the lever  86  and rotate the lever  86  from the locked position  106  to the unlocked position  108 . During rotational movement of the lever  86 , the second spring  116  is compressed and the pin  104  of the cam portion  100  acts against the slot  102  of the cam follower portion  98 . In response to the rotation of the lever  86  and the movement of the pin  104  against the slot  102 , the tip  96  of the pin  84  moves out of the slot  90 . 
     When the tip  96  is retracted out of the slot  90 , the operator of the vehicle can rotate the tilt housing  86  (which is associated with a steering wheel) relative to the inner column jacket  14  and select a desired orientation of the tilt housing  16 . When the operator has selected the desired orientation of the tilt housing  16  relative to the inner column jacket  14 , the operator can release the gripping portion  118  and the second spring  116  will expand and urge the pin  104  toward an end  120  of the slot  102 , shown in  FIG. 8 . In response to rotation of the lever  86  from the unlocked position  108  to the locked position  106 , the cam follower portion  98  will move toward the transverse projection  68  and the tip  96  of the pin  84  will be inserted in the slot  90 , locking the tilt housing  16  with respect to the inner column jacket  14 . 
     While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.