Abstract:
A recliner mechanism includes a cylindrical element attached to a back portion and a conically shaped element attached to a seat portion. The cylindrical element has an axially extending central opening formed therein defined by a conically tapered inner surface, and the conically shaped element has an outer surface receivable within the central opening. The conically shaped element is movable in an axially inward direction to a locked orientation with the inner surface of the cylindrical element engaging the outer surface of the conically shaped element to inhibiting relative pivotal movement of the back portion and the seat portion. The conically shaped element is also movable in an axially outward direction to an unlocked orientation with the inner surface of the cylindrical element disengaged from the outer surface of the conically shaped element to permitting relative pivotal movement of the back portion and the seat portion.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/238,584, filed Oct. 6, 2000. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to seating devices. 
     More particularly, the present invention relates to adjustment mechanisms for seating devices. 
     In a further and more specific aspect, the present invention concerns adjustment mechanisms for vehicle seating. 
     2. The Prior Art 
     Within the art of recliner mechanisms for vehicle seating, many and diverse devices have been developed. These devices often function satisfactorily for the actual reclining function, but function poorly in the area of safety. Typically, when a force of a specific magnitude, such as from a collision, is applied to a seat back, the seat has a catastrophic failure. In other words, the seat back remains more or less rigid and supportive until a certain level of force is exceeded. When this level is reached, the recliner mechanism breaks, letting the seat back pivot unrestrained. When this failure occurs, injury to the occupant of the seat can result. In many automobiles, the space allocated for a recliner mechanism is very limited. By reducing size and cost, current recliner mechanisms are often less than robust and fail at the application of relatively low forces. With the increase of restraint belts, which attach to the seat back, forces applied to the seat back in a collision will only increase. 
     It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art. 
     Accordingly, it is an object the present invention to provide a recliner mechanism which is extremely rugged and which fixedly holds the seat back relative to the seat portion. 
     It is another object the present invention to provide an embodiment of the recliner mechanism which clutches under a specified load. 
     SUMMARY OF THE INVENTION 
     Briefly, to achieve the desired objects of the present invention in accordance with a preferred embodiment thereof, provided is a recliner mechanism for a seat frame including a back portion and a seat portion. The recliner mechanism includes an internal conically shaped element attached to either the back portion or the seat portion and a mating external conically shaped element attached to the other of the back portion and the seat portion. The inner and outer surfaces of the internal and external conically shaped elements, respectively, can have mating gears formed therein to provide positive braking action or the outer surfaces can be smoother to provide a clutching action. Cam surfaces are provided on an axle for the external conically shaped element and a recliner lever moves the cam surfaces to cam the external conically shaped element into engagement with the internal conically shaped element in a first or locked position and out of engagement in a second or reclining position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Specific objects and advantages of the instant invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment thereof taken in conjunction with the drawings, in which: 
     FIG. 1 is a perspective view of a seat frame and recliner mechanism incorporating the present invention; 
     FIG. 2 is an exploded perspective view of a portion of the seat frame and recliner mechanism of FIG. 1; 
     FIG. 3 is an enlarged perspective view, similar to FIG. 2, illustrating the various components of the recliner mechanism in more detail; 
     FIGS. 4 and 5 are sectional views of the portion of the seat frame and recliner mechanism illustrated in FIG. 2, in the unlocked and locked orientations, respectively; 
     FIG. 6 is a greatly enlarged perspective view of a portion of the recliner mechanism mounting apparatus; 
     FIG. 7 is a side view of the recliner mechanism mounting apparatus illustrated in FIG. 6, showing an energy absorption feature; 
     FIG. 8 is a perspective view of one side of a seat frame and recliner mechanism incorporating another embodiment of the present invention; 
     FIG. 9 is an exploded perspective view of a portion of the seat frame and recliner mechanism of FIG. 8; 
     FIG. 10 is an enlarged perspective view, similar to FIG. 9, illustrating the various components of the recliner mechanism in more detail; and 
     FIG. 11 is an enlarged perspective view illustrating the camming system of the recliner mechanism of FIG.  8 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning now to the drawings in which like reference characters indicate corresponding elements throughout the several views, attention is first directed to FIG. 1 which illustrates a seat frame  10  of a seating mechanism for use in vehicles. Seat frame  10  includes a track assembly  12  having an inner track  14  and an outer track  16 . Outer track  16  is reciprocally movable upon inner track  14  by employing a latch mechanism  18 . Reciprocal movement of outer track  16  permits adjustment of a seat as is commonly employed in commercial and private vehicles. Substantially any latch mechanism can be employed, however in the preferred embodiment, a latch mechanism as disclosed in pending application ADJUSTABLE SUPPORT APPARATUS AND ARCHITECTURE FOR ADJUSTING SUPPORT APPARATUS, Ser. No. 09/092,675, is employed. 
     Outer track  16  includes a rearward end  20  to which a back frame  22  is pivotally attached. In this embodiment, rearward end  20  is an integral portion of outer track  16 . It will be understood that often a back frame is attached to the track via a riser or bracket which is a separate element. This can also be utilized in the present invention. Back frame  22  includes an out board member  24  and an in board member  26 . Out board member  24  is pivotally coupled to end  20  on the out board side of track assembly  12  by means of reclining mechanism  28 . Reclining mechanism  28  allows for adjustment in the positioning of back frame  22 , as will be described in more detail presently. It will be understood by those skilled in the art that while, in the present embodiment, reclining mechanism  28  is coupled to the out board side of seat frame  10  and a free pivot is located on the in board side of seat frame  10 , this is simply convention, and they may be reversed as desired. 
     Turning now to FIG. 2, the out board side of frame  10  and reclining mechanism  28  are shown in an exploded view to better illustrate the various components and their relationships. As can be seen best in FIG. 2, outer track  16  includes an out board member  16   a  and an in board member  16   b , illustrated in an exploded or separated position. Also, outboard member  24  of seatback  22  includes an outer element  24   a  and a mating inner element  24   b , illustrated in an exploded or separated position. 
     Referring additionally to FIG. 3, it can be seen that reclining mechanism  28  includes a cylindrically shaped element  30  having an axially extending central opening therethrough with a conically tapered or shaped inner surface  31 . In this embodiment, surface  31  tapers conically from a larger opening at the right side (in FIG. 2 or  3 ) to a smaller opening in the left side. Also, surface  31  is fabricated with gear-like teeth or ridges (illustrated specifically at  32 ) in this embodiment to form a positive acting reclining brake mechanism. However, as will be explained in more detail below, surface  31  can be fabricated relatively smooth (as illustrated specifically at  33 ) to form a clutch type of mechanism. Element  30  is fixedly attached to outer element  24   a  and inner element  24   b  of seatback  22  by means of bolts (not shown) extending through holes  35  in outer element  24   a , element  30 , and inner element  24   b.    
     Reclining mechanism  28  further includes a conically shaped element  37 , which in this brake embodiment is fabricated with complemental ridges or gear teeth  38  in the outer periphery thereof. Element  37  is fabricated to be positioned within element  30  so that gear teeth  32  of element  30  mate or mesh with gear teeth  38  of element  37  to positively prevent relative rotary movement between elements  30  and  37 . Element  30  is constructed with four holes  39  extending axially therethrough. Four slider pins  40  are provided for mounting element  30  between out board member  16   a  and in board member  16   b.    
     A pair of mounting plates  42  and  43  (see FIGS. 4 and 5) are provided and positioned at the outer surfaces of out board member  16   a  and in board member  16   b , respectively. Mounting plates  42  and  43  each have four slotted holes  45  formed therein with an enlarged portion adjacent one end for receiving slider pins  40  and a smaller portion adjacent the other end. In the assembled orientation, slider pins  40  extend through holes  39  in element  37  and element  37  is positioned coaxially in the opening in element  30 . One end of each of slider pins  40  extends through the enlarged portion of slotted holes  45  in mounting plate  42 . Also, the other end of each of slider pins  40  extends through the enlarged portion of slotted holes  45  in mounting plate  43 . The one or both ends of slider pins  40  are threaded and nuts are engaged to hold the assembly fixedly in place. Mounting plates  42  and  43  may be fixedly attached to members  16   a  and  16   b  by some means, such as welding or the like, or they may simply be held in place by slider pins  40  extending through holes in members  16   a  and  16   b.    
     Here it should be noted that element  37  is shorter, axially, than element  30  and is free to slide axially along slider pins  40  a limited distance. Further, when element  37  is moved axially inwardly the full extent (locked orientation) it is positioned so that gears  33  in element  30  mesh with gears  38  on element  37 , and when element  37  is moved axially outwardly the full extent (unlocked or reclining orientation) it is positioned so that gears  33  in element  30  do not mesh with gears  38  on element  37 . 
     An axle  50  is constructed to extend through an axial hole  51  in element  37  and through axial holes  52  in mounting plates  42  and  43 . Axle  50  is longer than slider pins  40  so as to extend outwardly from mounting plate  42  a short distance. A bearing sleeve  53  is positioned coaxially over the outwardly extending end of axle  50  (see FIGS. 4 and 5) and a recliner handle  55  is engaged on axle  50  by means of a nut threadedly engaged on the end of axle  50 . Bearing sleeve  53  allows for relative movement between recliner handle  55  and mounting plate  42 . 
     Recliner handle  55  has a pair of inwardly extending pins  56  attached thereto so as to extend through slotted openings  57  in mounting plate  42  and into openings  58  in the end of element  37 . Openings  58  have sloping or cam shaped inner surfaces. Also, the inner ends of pins  56  are rounded to form cam engaging surfaces that are positioned to engage the cam shaped inner surfaces of openings  58 . The cam surfaces of openings  58  are formed so that as recliner handle  55  is lifted or rotated upwardly (see FIG.  4 ), element  37  is cammed axially outwardly out of engagement with element  30  and seat back  22  is free to rotate between an upright and a reclining position. Once seat back  22  is positioned in the desired position, recliner handle  55  is lowered or rotated downwardly (see FIG. 5) and element  37  is cammed inwardly into engagement with element  30 , which locks seatback  22  positively in the selected position. 
     In some embodiments it may be desirable to provide a compression spring  62  on axle  50  so as to provide a bias on element  37  tending to force element  37  into the unlocked position. In this embodiment, handle  55  may only cam element  37  into the locked position and, when released, spring  62  biases element  37  into the unlocked position. Here it will be understood that many different types of camming or axial movement systems may be developed to move elements  30  and  37  between locked and unlocked positions and the illustrated systems are simply for exemplary purposes. 
     Referring additionally to FIG. 6, a greatly enlarged view of mounting plate  42  and the various openings described above is illustrated. From this view, the orientation of the various openings and the operation thereof can be more fully appreciated. 
     Turning now to FIG. 7, an even greater enlarged view of mounting plate  42  is illustrated. In particular, this view shows one of the slotted holes  45  and an associated slider pin  40  in greater detail. As explained briefly above, at least one of the slotted holes  45  is formed so that the width at one end is approximately equal to the diameter of an associated slider pin  40 . However, the width of slotted hole  45  tapers very gradually towards the opposite end so as to be somewhat smaller than the diameter of the associated slider pin  40 . Thus, associated slider pin  40  can be easily engaged through the enlarged end of the slotted hole  45  for the assembly of recliner mechanism  10 . 
     Under normal operating conditions or usage, the associated slider pin  40  is firmly attached to mounting plates  42  and  43  through the enlarged end of slotted hole  45 . During a forward crash, a large force is applied to the associated slider pin  40  forcing it into the smaller portion of the slot, as illustrated in dotted lines in FIG.  7 . As slider pin  40  moves into the smaller portion of slotted hole  45 , metal is stretched/compressed/deformed, which translates into substantial energy absorption. Here it will be understood that all four slotted openings  45  can be constructed in this fashion or only the openings extending in the direction of a potential crash. 
     In a somewhat different embodiment, the inner surface  31  of element  30  is formed so as to be relatively smooth (see surface  33  in FIG.  3 ). Similarly, the outer surface of element  37  is relatively smooth. In this embodiment, reclining mechanism  10  operates like a clutch, rather than a positive brake. As element  37  is cammed or otherwise moved axially inwardly into engagement with element  30 , a frictional engagement between the engaging inner and outer surfaces slows and ultimately prevents relative rotary movement. The “relatively smooth” inner surface of element  30  and the “relatively smooth” outer surface of element  37  could be for example, smooth metal or other hard material, rough metal or other hard material, rubber or other pliable soft material, etc. The amount of clutching movement or braking desired can be provided by the amount of relative axial movement provided between elements  30  and  37 . 
     Turning now to FIG. 8, another embodiment of a recliner mechanism  110  is illustrated. An out board member  124  of a back portion is pivotally coupled to end  125  on the out board side of a seat portion by means of reclining mechanism  110 . The back portion and the seat portion are not illustrated in greater detail, as they can be similar to those described in the previous embodiment. Reclining mechanism  110  allows for adjustment in the positioning of the back frame, as will be described in more detail presently. As stated in the previous embodiment, it will be understood by those skilled in the art that while, reclining mechanism  110  is coupled to the out board side of the seat frame, this is simply convention, and reclining mechanism may be reversed as desired. 
     Turning now to FIG. 9, the out board member  124  and reclining mechanism  110  are shown in an exploded view to better illustrate the various components and their relationships. As can be seen best in FIG. 9, the outboard element of the seat portion includes an out board member  116   a  and an in board member  116   b , illustrated in an exploded or separated position. Also, outboard member  124  of the seatback includes an outer element  124   a  and a mating inner element  124   b , illustrated in an exploded or separated position. 
     Referring additionally to FIG. 10, it can be seen that reclining mechanism  110  includes a cylindrically shaped element  130  having an axially extending central opening therethrough with a conically tapered or shaped inner surface  131 . In this embodiment, surface  131  tapers conically from a larger opening at the right side (in FIG. 9 or  10 ) to a smaller opening in the left side. Also, surface  131  is fabricated with gear-like teeth or ridges  132  in this embodiment to form a positive acting reclining brake mechanism. However, as will be explained in more detail below, surface  131  can be fabricated relatively smoothly to form a clutch type of mechanism. Element  130  is fixedly attached to outer element  124   a  and inner element  124   b  of the seatback by means of bolts (not shown) extending through holes  135  in outer element  124   a , element  130 , and inner element  124   b.    
     Reclining mechanism  110  further includes a conically shaped element  137 , which in this embodiment is fabricated with complemental ridges or gear teeth  138  in the outer periphery thereof. Element  137  is fabricated to be positioned within element  130  so that gear teeth  132  of element  130  mate or mesh with gear teeth  138  of element  137  to positively prevent relative rotary movement between elements  130  and  137 . Three slider pins  140  are provided for slidably mounting element  137  between out board member  116   a  and in board member  116   b.    
     Here it should be noted that element  137  is free to slide axially along slider pins  140  a limited distance. Further, when element  137  is moved axially inwardly the full extent (locked orientation) it is positioned so that gears  133  in element  130  mesh with gears  138  on element  137 , and when element  137  is moved axially outwardly the full extent (unlocked or reclining orientation) it is positioned so that gears  133  in element  130  do not mesh with gears  138  on element  137 . 
     An axial movement system is coupled to conical element  137  for moving it between the locked orientation and the unlocked orientation. In this embodiment, the axial movement system includes a cam assembly  145  carried by an axle  150  concurrently extending through the central opening of cylindrical element  130  and an axial hole  151  formed in conical element  137 . Shaft or Axle  150  is fixedly attached to in board member  116   b  and passes through an opening in out board member  116   a  as can be seen with momentary reference back to FIG.  8 . 
     Referring to FIGS. 10 and 11, cam assembly  145  includes a cam surface  148  slidably carried by axle  150  adjacent conical element  137  and a cam  149  rotatably carried by axle  150  and movable along cam surface  148 . As cam  149  is rotated by handle  154 , cam surface  148  is forced axially inwardly against conical element  137  moving element  137  into the locked orientation. When the rotation of cam  149  is reversed, element  137  is permitted to return to the unlocked orientation. A disengagement spring  158  is positioned between a back plate  159  and element  137  for biasing element  137  axially outwardly into the unlocked orientation. 
     Various changes and modifications to the embodiments herein chosen for purposes of illustration will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention, they are intended to be included within the scope thereof, which is assessed only by a fair interpretation of the following claims.