Abstract:
A head restraint assembly ( 16 ) comprising at least one post ( 20 ) having at least one retainer notch ( 52 ) and a tubular bushing ( 22 ) having a head ( 26 ) with a socket ( 32 ) and a bore ( 24 ) having longitudinal ribs ( 71 ) and sized to receive the at least one post ( 20 ). A button subassembly ( 38 ) which is insertable into the socket ( 32 ) is also provided. The button subassembly ( 38 ) is movable within the socket ( 32 ) such that an tongue ( 48 ) is movable in and out of alignment with an associated retainer notch ( 52 ) to allow the at least one post ( 20 ) to move. A method of attaching a head restraint assembly having a head restraint pad to a seat back is also disclosed.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a head restraint assembly for motor vehicle seats for enabling a head restraint pad to be moved with respect to a motor vehicle seat. 
     2. Background Art 
     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. 
     U.S. Pat. No. 4,854,642 to Hoover Universal, Inc., discloses a head restraint guide assembly having a bushing member installed within the seat back 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 seat back 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 is used which can be depressed from outside of the seat back 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. Additionally, once the bushing member is inserted into the seat, it is not removable. 
     The invention disclosed in U.S. Pat. No. 6,099,077, issued to Isaacson and assigned to Centura Group, Inc., solves many of those problems. The present invention offers further improvements in the function and manufacture of a head restraint assembly. 
     SUMMARY OF THE INVENTION 
     According to the present invention, an improved head restraint assembly is provided for enabling a head restraint pad to be moved with respect to a motor vehicle seat. The head restraint pad includes at least one post connected to and supporting the head restraint pad, and having at least one retainer notch for vertically adjusting the height of the head restraint pad. 
     In one aspect of the invention, a head restraint assembly, enabling a head restraint pad to be moved with respect to a motor vehicle seat back, is provided. The assembly has at least one post connected to and supporting the head restraint pad to permit the pad to be moved inwardly and outwardly in relation to the seat back. The at least one post has at least one retainer notch on the exterior surface of the at least one post. A tubular bushing is mounted to the seat and has an inside bore sized for receiving the at least one post. The inside bore has at least one longitudinal rib therein to guide the post so as to facilitate ready insertion thereof during manufacturing processes and inwardly and outwardly movement during operational use. The tubular bushing has a head outside the seat and the head has a socket with an open outside end. A button subassembly insertable into the open outside end of the socket is also provided. The button subassembly has an insertable end that inserts into the open outside end of the socket, an actuator portion located at the opposite end of the button subassembly from the insertable end which remains outside of the socket when the button subassembly is installed, and a central portion inserted into the socket through which the at least one post extends. The button subassembly further includes a spring located proximate the insertable end. The actuator portion is movable with respect to the head after the button subassembly is inserted into the socket. The button subassembly comprises a tongue adapted to cooperate with an associated retainer notch provided on the at least one post when the at least one post is moving inwardly or outwardly. The tongue is movable out of alignment with the associated retainer notch when the actuator portion is moved so that the head restraint pad may be moved with respect to the motor vehicle seat. 
     According to another embodiment of the present invention, the head restraint assembly comprises a pair of locking members, each having an undercut and wherein the spring comprises a pair of openings sized to engage the locking members. The spring is removably attached to the button subassembly by being installed over the locking members and constrained in the undercuts. 
     According to yet another embodiment of the present invention, one of the socket or the button subassembly has a flange. 
     According to yet another embodiment of the present invention, one of the socket or the button subassembly has a flange and the other of the socket or button subassembly has a groove sized to receive the flange. 
     According to a further embodiment of the present invention, the head has a bottom surface having an opening therein and the button subassembly has a flexible locking rib wherein the locking rib extends through the opening of the bottom surface of the head to selectively lock the button subassembly in the head. 
     According to a further embodiment of the present invention, the spring is integrally molded to the insertable end of the button subassembly. 
     Another aspect of the present invention provides a head restraint assembly enabling a head restraint pad to be moved with respect to a motor vehicle seat back. The assembly comprises at least one post connected to and supporting the head restraint pad to permit the pad to be moved inwardly and outwardly in relation to the seat back. The at least one post has at least one retainer notch on the exterior surface of the at least one post. A tubular bushing is mounted to the seat and has an inside bore sized for receiving the at least one post. The tubular bushing has a head outside the seat and the head has a socket with an open outside end. The invention provides a button subassembly insertable into the open outside end of the socket. The button subassembly has an insertable end that inserts into the open outside end socket, an actuator portion at the opposite end of the button subassembly from the insertable end which remains outside of the socket when the button subassembly is installed, and a central portion inserted into the socket through which the at least one post extends. The button subassembly further includes a spring located proximate the insertable end. The actuator portion is movable with respect to the head after the button subassembly is inserted into the socket. The button subassembly comprises a tongue adapted to cooperate with an associated retainer notch provided on the at least one post when the at least one post is moving inwardly or outwardly. The tongue is movable out of alignment with the associated retainer notch when the actuator portion is moved so that the head restraint pad may be moved with respect to the motor vehicle seat. The socket or the button subassembly has a flange. 
     In another embodiment of the present invention, the other of the socket or the button subassembly has a groove sized to receive the flange. 
     In an alternative embodiment of the present invention, the spring in integrally molded to the insertable end of the button subassembly. 
     According to another alternative embodiment of the present invention, the head restraint assembly comprises a pair of locking members each having an undercut and wherein the spring comprises a pair of openings sized to fit over the locking members. The spring is removably attached to the button subassembly by being installed over the locking members and constrained in the undercuts. 
     Yet another aspect of the present invention provides a method of attaching a head restraint assembly having a head restraint pad to a seat back. The method comprises attaching at least one post to the head restraint pad for supporting the head restraint pad and to permit the pad to be moved inwardly and outwardly in relation to the seat back. The at least one post has at least one retainer notch on the exterior surface of the at least one post. A tubular bushing is provided for attachment to the seat. The tubular bushing has an inside bore sized for receiving the at least one post and the inside bore has at least one longitudinal rib therein to guide the post so as to facilitate ready insertion thereof during manufacturing processes and inwardly and outwardly movement during operational use. The tubular bushing has a head outside the seat. The head has a socket with an open outside end. A button subassembly is inserted into the open outside end of the socket. The button subassembly has an insertable end that inserts into the open outside end of the socket; an actuator portion located at an opposite end of the button subassembly from the insertable end, the actuator portion remaining outside the socket when the button subassembly is installed, the actuator portion being movable with respect to the head after the button subassembly is inserted into the socket; a central portion inserted into the socket through which the at least one post extends; a spring located proximate the insertable end; and a tongue adapted to cooperate with an associated retainer notch provided on the at least one post when the at least one post is moving inwardly or outwardly. The tongue is movable out of alignment with the associated retainer notch when the actuator portion is moved so that the head restraint pad may be moved with respect to the motor vehicle seat. The tubular bushing is mounted to the seat. 
     A further aspect of the invention provides a method of attaching a head restraint assembly having a head restraint pad to a seat back. The method comprises connecting at least one post to the head restraint pad for supporting the head restraint pad and to permit the pad to be moved inwardly and outwardly in relation to the seat back. The at least one post has at least one retainer notch on the exterior surface of the at least one post. A tubular bushing is provided that is mountable to the seat and has an inside bore sized for receiving the at least one post. The tubular bushing has a head outside the seat. The head has a socket with an open outside end. A button subassembly is inserted into the open outside end of the socket, the button subassembly has an insertable end that inserts into the open outside end socket; an actuator portion located at the opposite end of the button subassembly from the insertable end, the actuator portion remaining outside of the socket when the button subassembly is installed, the actuator portion being movable with respect to the head after the button subassembly is inserted into the socket; a central portion inserted into the socket through which the at least one post extends; a spring located proximate the insertable end; and a tongue adapted to cooperate with an associated retainer notch provided on the at least one post when the at least one post is moving inwardly or outwardly. The tongue is movable out of alignment with the associated retainer notch when the actuator portion is moved so that the head restraint pad may be moved with respect to the motor vehicle seat. One of the socket or the button subassembly has a flange and the other of the socket or the button subassembly has a groove sized to receive the flange. The tubular bushing is mounted to the seat. 
     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 
     FIG. 1 is a perspective view of a motor vehicle seat of the type having a separate adjustable head restraint assembly; 
     FIG. 2 is an exploded view of the head restraint assembly according to the present invention; 
     FIG. 3 is a top plan view of the head restraint assembly; 
     FIG. 4 is a cross-sectional view of the head restraint assembly taken along line  4 — 4  of FIG. 3; 
     FIG. 5 is an enlarged cross-sectional view of part of FIG. 4, showing movement of the latch member between a latched and unlatched position; 
     FIG. 6 is a cross-sectional view of the tubular bushing showing longitudinal ribs taken along line  6 — 6  of FIG. 4; 
     FIG. 7 is a plan view of the button subassembly of the present invention having a molded over spring; 
     FIG. 8 is a perspective view of the button subassembly of the present invention having an insert molded spring; and 
     FIG. 9 is a perspective view of the button subassembly showing grooves and flanges on the insert and socket. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to FIG. 1, there is shown a perspective view of a motor vehicle seat  10  having a bottom cushion  12  and a seat back  14 . A head restraint assembly  16  is carried by the seat back  14  and has a pad  18  and a pair of downwardly extending mounting posts  20 . 
     FIGS. 2 through 9 illustrate the head restraint assembly  16 . The head restraint assembly  16  is provided to enable the pad  18  to be moved inwardly and outwardly in relation to the motor vehicle seat  10 , and includes at least one tubular bushing  22 , preferably made of plastic, mounted to the seat back  14 . Preferably, one tubular bushing  22  is provided for each post  20 . Each tubular bushing  22  has an inside bore  24  larger than the diameter of the post  20  for receiving the post  20 . The bushing  22  further includes a head  26  formed at the upper end thereof which engages the outside of the seat back  14  when mounted to the seat  10 . Preferably the seat back  14  includes a frame member  28  having an opening  30  larger than the tubular bushing  22  for receiving at least a portion of the tubular bushing  22 . 
     As illustrated in FIGS. 2 and 3, the head  26  has a socket  32  exposed to the bore  24  at a first end  34 , and outwardly accessible at a second end  36 . A button subassembly  38  having an insertable end  37  is insertable into socket  32  through the accessible second end  36  and includes a spring  40  located on one side of the bore  24  proximate the insertable end  37 , and an actuator portion  42  located on the opposite end of the button subassembly from the insertable end and exposed at the accessible second end  36  of the head  26 . The button subassembly has a central portion  39  through which the post  20  extends therethrough. In the preferred embodiment, the actuator portion  42  is provided with at least one protrusion  44  insertable into at least one aperture  46  formed on the spring  40 , thereby removably connecting spring  40  and actuator  42  together. Additionally, the button subassembly  38  is configured to conform to the head  26  at the accessible second end  36  in the illustrated arrangement so that a flush engagement results when the actuator portion  42  is moved with respect to the head  26 . 
     Further, in the preferred arrangement, the spring  40  is provided with a tongue or saddle portion  48  and legs  50 . Upon insertion of the button subassembly  38 , the spring  40  is positioned on one side of the bore  24  with legs  50  contacting the first end  34  of the socket  32 , and actuator  42  positioned on the opposite side of bore  24  exposed at the accessible second end  36  of socket  32 . 
     Preferably, the spring  40  is made out of a spring steel. However, one skilled in the art could manufacture the spring out of other materials such as other metals or polymers. 
     The operation of button subassembly  38  may be understood upon reference to FIGS. 3 and 4. The post  20  is formed with at least one retainer notch  52  on its exterior surface. When more than one retainer notch  52  is provided, they are preferably aligned on one side of post  20 . The tongue or saddle portion  48  is biased into alignment with the associated notch  52  provided along post  20  when post  20  is moving longitudinally. 
     The head restraint pad  18  may be moved inwardly or outwardly with respect to the seat  10  by moving actuator  42  into the socket  32  with the push of a finger, in turn compressing the legs  50  of the spring  40  and moving the tongue or saddle portion  48  out of alignment with the associated notch  52 . The pad  18  can then be moved inwardly and outwardly within the bore  24  until the desired height is reached. The actuator  42  is released and the tongue or saddle portion  48  is again in alignment with a different notch  52 . 
     In the preferred arrangement, it is desirable to retain the button subassembly  38  within the socket  32  while permitting the actuator  42  to be moved radially with respect to the head  26 . This is accomplished by providing a locking rib tab  53  formed on the actuator  42  and a longitudinal slot  55  formed on the head  26  at the accessible second end  36 . The locking rib  53  is movable within the slot  55  thereby limiting the transverse movement of actuator  42  so that button subassembly  38  is not unintentionally removed from the socket  32 . Alternatively, the locking rib  53  may be formed on the head  26  and the slot  52  may be formed on the actuator  42 , accomplishing the same result. 
     In order to secure the bushing  22  into the seat back  12 , the frame  28  is provided with a bore  54  extending from opening  30  and terminating at a length shorter than the length of the tubular bushing  22  to define a keeper  56 . The tubular bushing  22  further defines a latch member  58  movable between a latched position A and an unlatched position B as shown in FIG.  5 . The latch  58  includes a ramp surface  60  and a radial shoulder  62 . Upon assembly, when the bushing  22  is inserted into the frame bore  54 , the ramp surface  60  engages the frame bore  54  until radial shoulder  62  abuts the keeper  56 . Next, the post  20  is inserted into the bore  24  thereby locking the latch  58  into latched position A and thereby anchoring bushing  22  into seat frame  28 . 
     In use, the bushing  22  may be removed from the seat frame  28  by first removing the post  20  from the bore  24  causing the latch  58  to collapse into the unlatched position B as shown in FIG.  5 . This allows the bushing  22  to be removed from the seat frame  28  if so desired. 
     In order to assure that bushing  22  is inserted into frame bore  54  in the same orientation upon repeated insertion, an orientation locator projection  64  is formed on the tubular bushing  22 . The locator projection  64  is insertable into a slot portion  66  provided on the frame bore  54 . Additionally, in order to assure that the bushing  22  is snugly fit into the frame bore  54 , at least one rib  68  may be provided on tubular bushing  22  for localized, yet circumferentially distributed frictional engagement with the seat frame bore. 
     The bushing  22  preferably comprises a plurality of longitudinal ribs  71  within bore  24  to facilitate ready insertion thereof during manufacturing processes and inwardly and outwardly movement during operational use as shown, for example, in FIGS. 2,  3 ,  4  and  6 . 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  would 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  and the ribs  71  contact the mounting post to equalize and maintain efforts between the bushing  22  and the mounting post. 
     Referring now to FIG. 7, a second embodiment of the button subassembly  38  is shown. In this embodiment, the spring  40  is molded to the actuator  42  during the molding process. A plastic bridge  41  encapsulates the spring  40  about the tongue or saddle portion  48 . This prevents any metal-to-metal contact between the spring  40  and post  20 , thereby decreasing noise and rattle. In this embodiment, the plastic ridge  41  may be the tongue that cooperates with the notch  52 . 
     Referring now to FIG. 8, a third embodiment of the button subassembly  38  is shown. In this embodiment, the spring  40  is a simple wire molded to the actuator  42  during the molding process. The spring  40  comprises a tongue or saddle portion  48  and legs  50 . The tongue or saddle portion  48  may be exposed or encapsulated with plastic to prevent metal to metal plastic and cooperate with the notch  52 . Further, as discussed above, the spring  40  may be manufactured out of a polymer to prevent metal to metal contact between the post  20  and the spring. 
     Due to manufacturing tolerances, the actuator  42  occasionally rattles in socket  32 . Additionally, the actuators  42  may be inserted into the socket  32  upside down. In an effort to improve the performance and manufacture of the product, a flange  47  may be added to either the socket  32  or the actuator  42  to facilitate the ready movement of the button subassembly in the socket. Preferably, flanges  47  and grooves  49  added to the socket  32  and the actuator  42  as shown in FIG.  9 . In the illustrated embodiment, grooves  49  are shown on the bottom surface  80  of the socket. Corresponding flanges  47  are shown on the bottom surface  82  of the actuator which align with the grooves  49 . The flanges  47  and grooves  49  prevent the actuator from being inserted upside down. Additionally, the sidewalls  84  of the socket  32  are angled and the sidewalls  86  of the actuator are correspondingly angled so that the bottom surfaces  80 ,  82  are wider than the upper surfaces  88 ,  90  to further minimize the chance that the actuator is inserted upside down. Alternatively, the flanges may be in the socket  32  and the grooves on the actuator. Further, the flanges and grooves may be located on the top, side or bottom walls. 
     In order to improve the grip of the actuator, protrusions  92  may be added to the actuator  42 , as shown in FIG.  9 . Similarly, a depression  94  may be added to the actuator  42  to improve the grip on the actuator as shown in FIG.  2 . 
     As shown in FIG. 9, the socket  32  has a bottom surface  80  and the actuator has a bottom surface  82 . Preferably, the bottom surface  82  of the actuator is approximately in the same plane as the bottom surface  80  of the socket to prevent material from getting pinched between the actuator and the socket when the actuator is pushed in. 
     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.