Abstract:
An adjustable head restraint assembly and method for enabling a head restraint pad ( 18 ) to be adjustably and lockably positioned with respect to a motor vehicle seatback ( 14 ) so that the head restraint pad remains in an adjusted position during a crash sequence after being set by a user. Associated with the head restraint pad ( 18 ) is a pair of posts ( 20 ). A tubular bushing subassembly ( 22 ) is mounted within the seatback ( 14 ). It has an inside bore ( 54 ) sized for receiving one of the at least one posts ( 20 ). The tubular bushing subassembly ( 22 ) has an upper separable portion ( 26   a ) with a customizable head ( 36 ), and a universal lower portion ( 26   b ).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of U.S. application Ser. No. 10/386,591 filed Mar. 12, 2003, to issue on Jun. 1, 2004 as U.S. Pat. No. 6,742,846, the disclosure of which is incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a universal head restraint assembly in motor vehicle seats for use with a head restraint pad that is lockably positioned with respect to a motor vehicle seatback.  
         [0004]     2. Background Art  
         [0005]     Motor vehicle seats typically include a head restraint pad mounted to the seat for comfort and safety of the passenger. The head restraint pad is mounted on one or two posts which are inserted into guide sleeves affixed to the seat. The posts typically include retainer notches which allow the head restraint pad to be vertically adjustable.  
         [0006]     U.S. Pat. No. 4,854,642 to Hoover Universal, Inc., discloses a head restraint guide assembly having a bushing installed within the seatback for receiving the head restraint pad posts. The head restraint bushing includes extending legs with ramp surfaces so that when the bushing is inserted within the seatback, the legs are resiliently deflected and become locked into place when the installed position is reached. The head restraint post passes through the bushing and has a number of notches which provide detents. A detent lug carried by the bushing engages the detent notches and is resiliently biased against the post. The detent notches are provided with cam surfaces, enabling the head restraint to be raised and lowered to and past the detent positions. The lowermost notch forms a retainer notch with a radial wall which prevents complete removal of the head restraint. A leaf spring actuator can be depressed from outside of the seatback and acts on the detent lug to deflect it out of engagement with the detent notches, thereby enabling withdrawal of the head restraint assembly. In order to remove the head restraint post, a downward force must be applied to the actuator by a tool such as a screwdriver, causing the lug to move out of engagement with the retainer notch.  
         [0007]     U.S. Pat. No. 6,099,077 discloses a head restraint assembly for a motor vehicle. It is commonly owned with the present application and is incorporated herein by reference. That reference discloses actuator springs within a button subassembly that may become over-stressed because their deflection is relatively unconstrained over repeated use.  
         [0008]     U.S. Pat. No. 5,667,276 discloses a locking headrest support assembly that includes two tines in the manner of a fork that extend from a sleeve. One tine is provided with a prong which is intended to prevent the extraction of the sleeve from a hole in the back of a vehicle seat. That tine is also provided with a locator rib which orients the sleeve in the proper direction within the hole in the vehicle seat. The other tine is provided with a side rib which provides the sleeve be tight fit in the hole in the vehicle seat.  
       SUMMARY OF THE INVENTION  
       [0009]     One objective of the present invention is to commonize one or more components of a head restraint assembly by providing some universal components in the assembly that the original equipment manufacturer or tier one supplier may place in a vehicle seatback, while other components in the assembly can be customized. The latter components can be variously shaped so that they can conform with the style of vehicle seat.  
         [0010]     Another objective of the invention is to provide a means to satisfy requirements mandated by a regulatory authority.  
         [0011]     According to the present invention, an improved head restraint assembly is provided for enabling a head restraint pad to be lockably positioned with respect to a motor vehicle seatback. The head restraint pad includes at least one post connected to and supporting the head restraint pad. A tubular bushing subassembly is mounted to the seat and has an inside bore sized for receiving the at least one post. The tubular bushing subassembly has a lower universal portion and a separable upper customizable portion. The lower portion is seated within the sleeve that is received within the vehicle seatback. The upper portion of the tubular bushing subassembly has a head outside the seat.  
         [0012]     The invention thus allows portions of the head restraint assembly to be commonized. This has the attribute of reducing tooling costs, which would otherwise be required to manufacture an entire subassembly when in fact the installer merely wishes to alter the appearance of the head of the upper portion (e.g., circular, oval, rectangular or square-shaped) as desired, to be in harmony with the style of vehicle seatback. Thus, the lower portion can be commonized among many vehicle platforms. It remains relatively unchanged.  
         [0013]     The above objects and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a perspective view of a motor vehicle seat of the type having a separate adjustable head restraint assembly;  
         [0015]      FIG. 2  is an exploded view of the tubular button subassembly of the head restraint assembly according to the present invention; and  
         [0016]      FIG. 3  is an assembled view of the head restraint assembly according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]     Referring now to  FIG. 1 , there is shown a perspective view of a motor vehicle seat  10  having a bottom cushion  12  and a seatback  14 . A head restraint assembly  16  including a pad  18  is supported by the seatback  14 . The assembly includes the pad  18  and a pair of downwardly extending mounting posts  20 .  
         [0018]      FIG. 2  illustrates various details of the head restraint assembly  16 . The head restraint assembly  16  enables the pad  18  to be moved inwardly and outwardly in relation to the motor vehicle seat  10 . Inserted into a sleeve  28  in the seatback is a tubular bushing subassembly  22 , preferably made of plastic. One tubular bushing subassembly  22  is provided for each post  20 . Each tubular bushing subassembly  22  has an inside bore  24  for receiving a post  20 .  
         [0019]     The bushing subassembly  22  further includes a head  36  formed at the upper end thereof which engages the outside of the seatback  14  when mounted to the seat  10 .  
         [0020]     The seatback  14  receives a sleeve  28  having an opening  30  that is larger than the tubular bushing subassembly  22  for receiving at least a portion thereof ( FIG. 2 ).  
         [0021]     Additional detail of the tubular bushing subassembly  22  will now be discussed with particular reference to  FIG. 2 . The tubular bushing subassembly  22  has a lower universal portion  26   b  and a separable customizable upper portion  26   a . The lower portion  26   b  and a part of the upper portion  26   a  are seated within the sleeve  28  that is received within the vehicle seatback  20 .  
         [0022]     The upper portion  26   a  of the tubular bushing subassembly  22  is detachably received by the lower portion  26   b . Accordingly, the upper portion  26   a  includes a lower portion-receiving section  100  and a means for registration  106 .  
         [0023]     In order to secure the tubular bushing subassembly  22  in relation to the seatback  14 , the sleeve  28  is provided with a bore  54  extending from opening  30  and terminating at a length shorter than the length of the tubular bushing subassembly  22 .  
         [0024]     The lower portion  26   b  of the tubular bushing subassembly  22  further defines a latch member  58  that is moveable between a latched position and a biased unlatched position. The latch  58  includes a ramp surface  60  and a radial shoulder  62 . Upon assembly, when the lower portion  26   b  is inserted into the bore  54 , the ramp surface  60  engages the bore  54  until the radial shoulder  62  engages a notched surface (not shown) within the bore  54 .  
         [0025]     Next, the upper portion  26   a  of the bushing subassembly  22  is moved into registration with the lower portion  26   b . To secure the portions  26   a ,  26   b , an inter-portion latching mechanism  104  is provided proximate an upper end of the lower portion  26   b . The latching mechanism  104  is received within an inner diameter of the upper portion  26   b  of the bushing subassembly  22 .  
         [0026]     After the upper portion  26   a  has been secured in relationship to the lower portion  26   b  to form an integrated tubular bushing subassembly  22 , the post  20  can be inserted into the bore  24 , thereby locking the latch member  58  and latching mechanism  104  into the latched positions and thereby anchoring the tubular bushing subassembly  22  into the sleeve  28  and seat back  14 .  
         [0027]     In use, the bushing subassembly  22  may be removed from the sleeve  28  by first removing the post  20  from the bore  24 , causing the latch  58  to revert to the biased unlatched position. This allows the bushing subassembly to be removed from the seat frame if desired.  
         [0028]     If desired, registration of the upper and lower portions  26   a ,  26   b  can be assured by providing a means for registration  106  therebetween. Thus, the disclosed design includes a detent provided in the lower or upper portion to assure registration of the upper and lower portions  26   a ,  26   b  as an example of the means for registration  106 . In practice, the means for registration  106  include a protrusion from the lower portion  26   b  that is received within a detent defined within the upper portion  26   a , or vice versa.  
         [0029]     In order to assure that the tubular bushing subassembly  22  is inserted into bore  54  in the same orientation upon repeated insertion, an orientation locator projection  64  is formed on the upper portion  26   a  of the tubular bushing subassembly  22 . The locator projection  64  is insertable into a slot portion  66  that is provided on the sleeve  28 . Additionally, in order to assure that the bushing subassembly  22  is snugly fit into the bore  54 , at least one rib  68  of the upper portion  26   a  may be provided for localized, yet circumferentially distributed frictional engagement with the seat frame bore  54 .  
         [0030]     The bushing subassembly  22  preferably comprises a plurality of longitudinal ribs  71  within bore  24  in order to facilitate ready insertion thereof during the manufacturing and assembly process. The number and spacing of the ribs  71  depends on several factors, including the length and curvature of the post  20 . Without the ribs  71 , the post  20  might occasionally bind or rattle within the bore  24  due to manufacturing tolerances. With the ribs  71 , the bore  24  is made slightly larger than the post  20 . The ribs  71  thus contact the mounting post to equalize and maintain efforts between the bushing  22  and the mounting post.  
         [0031]     Accordingly, there has been disclosed a solution to various requests that portions of the head restraint assembly be commonized. These generally are represented by the lower portion  26   b  of the bushing subassembly  22 . This has the attribute of reducing tooling costs, would otherwise be required to manufacture an entire subassembly when in fact the installer merely wishes to alter the appearance of the head  36  of the upper portion  26   a  (e.g., circular, oval, hexagonal, rectangular or square-shaped) as desired, to be in harmony with the style of vehicle seatback. One benefit of the invention is that the lower portion  26   b  can be commonized among many vehicle platforms. It remains relatively unchanged.  
         [0032]     There thus has been disclosed a bushing subassembly  22  with upper and lower portions  26   a ,  26   b  that are separable. In use, the upper portion  26   a  slides onto the lower portion  26   b  until an inter-portion latching mechanism  104  and the means for registration  106  engage.  
         [0033]     Thus, it is apparent that there has been provided, in accordance with the invention, an improved head restraint assembly for motor vehicle seats that fully satisfies the objects, aims and advantages as set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the following claims.