Abstract:
A suspension for a motor vehicle having a hollow suspension member including first and second spaced apart sidewalls and a pivot pin. In the preferred embodiment, the pivot pin is a locking assembly that includes a first retainer partially insertable through a first window formed in the first sidewall and a second retainer partially insertable through a second window formed in the second side wall. The first retainer engages the second retainer to present a pivot that receives a pivot arm between the sidewalls.

Description:
FIELD OF INVENTION 
       [0001]    This invention relates to a suspension link for a vehicle. In particular, this invention relates to a suspension link having an integral pivot assembly. 
       BACKGROUND OF INVENTION 
       [0002]    Vehicle suspension design has recently become increasingly complex due to greater demands from the user regarding a reduced tolerance for noise, vibration and/or harshness being transferred to the vehicle cabin from driveline or suspension components. Additionally, vehicles are becoming more commonly equipped with accessories such as power steering, power brakes, air conditioning, vehicle stability systems, anti-lock braking systems and the like. Each of these systems occupy space. Furthermore, power transmission systems have become increasingly complex with the advent of a variety of emission control systems and components as well as engine performance enhancing components. Based on these trends, space has become a premium. 
         [0003]    In one known vehicle suspension design, a suspension member is equipped with a Watts-type linkage assembly. A pivot arm of the Watts linkage assembly is rotatably coupled to a suspension member in a cantilevered fashion such that the pivot arm is positioned adjacent to the suspension member. A first Watts link is coupled to a first end of the pivot arm and a second Watts link is coupled to an opposite end of the pivot arm. Because the pivot arm is longitudinally offset from the suspension member, each Watts link includes an offset arm portion connected to the pivot arm. 
         [0004]    In at least one vehicle, the suspension member and the Watts linkage assembly are positioned between a well used to store a vehicle spare tire and a transmission housing. To maximize the amount of space available for adjacent components and/or storage areas, it may be desirable to minimize the volume of space occupied by the suspension components. Furthermore, it may be desirable to minimize or eliminate offset loading within the suspension components in an attempt to provide more robust structures. 
       SUMMARY OF INVENTION 
       [0005]    The suspension assembly of the present disclosure includes a frame, a suspension link having first and second ends movably coupled to the frame, a pivot arm rotatably coupled to the suspension link, a first link and a second link. The pivot arm is positioned within a cavity formed in the suspension link. The first link is coupled to a first end of the pivot arm. The second link is coupled to a second end of the pivot arm. 
         [0006]    In a first aspect of the invention, the pivot arm is a locking assembly. The locking assembly includes a fastener interconnecting first and second retainers. The suspension assembly further includes a first link being coupled to a first end of the pivot arm and a second link being coupled to a second end of the pivot arm. 
         [0007]    The present disclosure also provides a suspension for a motor vehicle having a hollow suspension member including first and second spaced apart side walls and a locking assembly. The locking assembly includes the first retainer partially insertable through a first window formed in the first sidewall and a second retainer partially insertable through a second window formed in the second side wall. The first retainer engages the second retainer and includes two radially extending and axially spaced apart first and second flanges capturing a portion of the first sidewall therebetween. 
         [0008]    In another form, a suspension for a motor vehicle includes a movable suspension link having a hollow portion with first and second spaced apart sidewalls. A pin is coupled to the suspension link and extends between the first and second sidewalls. A pivot arm is partially positioned within the hollow portion and rotatably supported by the pin. A first link is coupled to the first end of the pivot arm and a second link is coupled to a second end of the pivot arm. 
         [0009]    A method of making a suspension assembly is also disclosed. The suspension assembly includes a first link with a first shell and a second shell, a pivot arm having a first half and a second half, and a pin. The method includes fixing the first shell to the second shell to define a pocket within the first link. The pin is coupled to the first link and extends through the pocket. The first half and the second half of the pivot arm are positioned at diametrically opposed locations adjacent the pin. The first and second halves are interconnected to define a pivot arm rotatably supported by the pin. 
         [0010]    Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. In particular, it is contemplated that the claimed suspension may be used in conjunction with not only the Watts-type suspension previously described, but any suspension that connects the wheel carriers with a link such as a twist axle or a de Dion suspension. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0011]    The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
           [0012]      FIG. 1  is a partial bottom view of an exemplary vehicle equipped with a suspension described within the present disclosure; 
           [0013]      FIG. 2  is a perspective view of a portion of the suspension shown in  FIG. 1  according to the present invention; 
           [0014]      FIG. 3A  is a perspective view of a portion of an exemplary twist lock assembly according to the present disclosure; 
           [0015]      FIG. 3B  is a perspective view of a portion of an alternate twist lock assembly according to the present disclosure; 
           [0016]      FIG. 4  is a side view of an exemplary twist lock assembly according to the present disclosure; 
           [0017]      FIG. 5  is a partial fragmentary perspective view of the suspension having a portion of the compound link removed; 
           [0018]      FIG. 6  is a partial fragmentary cross-sectional view of the suspension taken along line  6 - 6  as shown in  FIG. 2 ; 
           [0019]      FIG. 7  is a partial fragmentary cross-sectional view of the suspension taken along line  7 - 7  shown in  FIG. 6 ; 
           [0020]      FIG. 8  is a cross-sectional view of suspension taken along line  8 - 8  shown in  FIG. 9  according to an alternate aspect of the present invention; and 
           [0021]      FIG. 9  is a partial fragmentary perspective view of the suspension of  FIG. 8  having a portion of the compound link removed. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0022]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
         [0023]    With reference to  FIG. 1 , a portion of an exemplary vehicle  10  includes a frame  12  and a suspension assembly  14 . A driveline  16  includes a transaxle  18  having a first output shaft  20  and a second output shaft  22 . A cross member  24  is mounted to frame  12  and supports transaxle  18 . 
         [0024]    Suspension assembly  14  includes a compound link  30  having a first end  32  and a second end  34 . A first spring  36  is positioned on a first spring seat  38  mounted to first end  32  of compound link  30 . A second spring  40  is positioned on a second spring seat  42 . Second spring seat  42  is fixed to second end  34  of compound link  30 . First spring  36  and second spring  40  is each positioned between compound link  30  and frame  12 . Accordingly, compound link  30  is movable relative to frame  12 . 
         [0025]    With reference to  FIGS. 1 and 2 , suspension assembly  14  also includes a pivot arm assembly  44  rotatably coupled to compound link  30 . A first link  46  includes a first end  48  coupled to a first portion  50  of pivot arm assembly  44 . A second end  52  of first link  46  is coupled to frame  12  via a bracket assembly  54 . In similar fashion, a second link  56  includes a first end  58  coupled to a second portion  60  of pivot arm assembly  44 . A second end  62  of second link  56  is coupled to frame  12  via a bracket assembly  64 . During vehicle operation, compound link  30  moves relative to frame  12 . In particular, first end  32  may move relative to frame  12  in the same or opposite direction and at the same or different magnitude as second end  34  moves relative to frame  12 . Lateral movement of compound link  30  relative to frame  12  is limited by pivot arm assembly  44 , first link  46  and second link  56 . 
         [0026]    As best shown in  FIGS. 2 to 7 , compound link  30  is a substantially hollow tubular structure having a substantially rectangular cross section. Compound link  30  includes a forward sidewall  100  and a rearward sidewall  102 . A top wall  104  interconnects one edge of forward sidewall  100  with one edge of rearward sidewall  102 . A bottom wall  106  interconnects opposite edges of forward sidewall  100  and rearward sidewall  102  to form a contiguously walled tube defining a cavity  108 . 
         [0027]    As shown, compound link  30  includes a first shell  110  welded to a second shell  112 . First shell  110  is a substantially channel-shaped member including forward sidewall  100 , a first lip  114  which forms a portion of top wall  104  and a second lip  116  which forms a portion of bottom wall  106 . Forward sidewall  100  interconnects first lip  114  and second lip  116 . Second shell  112  is substantially similar to first shell  110  and is a substantially channel-shaped member. Second shell  112  includes rearward sidewall  102 , a third lip  118  and a fourth lip  120 . Rearward sidewall  102  interconnects third lip  118  and fourth lip  120 . Third lip  118  forms a portion of top wall  104  while fourth lip  120  forms a portion of bottom wall  106 . Alternately, compound link  30  may be comprised of a single piece of tubular formed material instead of first shell  110  and second shell  112 . The forming process may include a process such as hydro-forming. 
         [0028]    An upper window  122  is formed in top wall  104  to provide clearance for second portion  60  of pivot arm assembly  44 . A lower window  124  is formed in bottom wall  106  to provide clearance for first portion  50  of pivot arm assembly  44 . A front window  126  is formed in forward sidewall  100  to provide clearance for a front retainer  128  of a twist lock retainer assembly  130 . A rear window  132  is formed in rearward sidewall  102  to provide clearance for a rear retainer  134  of twist lock retainer assembly  130 . Front window  126  is defined by first and second circumferentially spaced apart curved portions  135  and  136  having a first radius as well as third and fourth curved portions  138  and  140  having a second radius greater than the first radius. Each of the curved portions share a common center. Radially extending leg portions  141  interconnect the ends of the curved sections. Rear window  132  is substantially similar to front window  126  and includes first and second curved portions  142  and  143  having a first radius as well as third and fourth curved portions  144  and  146  having a second radius greater than the first radius and extending about a common center. Radially extending leg portions  147  interconnect the ends of the curved sections. 
         [0029]    A web portion  148  of compound link  30  extends between lower window  124  and front window  126 . Similar web portions  150 ,  152  and  154  extend between the remaining adjacent pairs of windows  122 ,  124 ,  126  and  132 . It should be appreciated that compound link bending strength is maintained due to the use of uninterrupted web portions  148 ,  150 ,  152  and  154 . 
         [0030]    Twist lock retainer assembly  130  acts as a pivot pin and pivotally supports the pivot arm  44 . The twist lock assembly  130  is substantially cylindrically-shaped and includes front retainer  128 , rear retainer  134 , and a socket-head cap screw  156 . Front retainer  128  includes a hollow cylindrical body  158 , a circular base flange  162 , a pilot portion  164  and a key flange  166 . Circular base flange  162  includes an outer surface  170 , an inner surface  172 , and a circumferential surface  174  extending therebetween. Circular base flange  162  has an outer diameter larger than the largest opening within front window  126 . As shown in  FIGS. 3A and 3B , ribs  176  or protrusions  178  may be formed on inner surface  172  to enhance torque/clamp load capacity on forward sidewall  100  of compound link  30 . Ribs  176  and protrusions  178  may be either raised or impregnated within circular base flange  162 . A chamfer (not shown) may be formed at the intersection of inner surface  172  and circumferential surface  174  to ease installation of front retainer  128 . The chamfer may be formed as a 15 degree lead and extend for approximately 1 to 2 mm radially inwardly about the entire circumference of circular base flange  162 . 
         [0031]    Key flange  166  is substantially similar in shape to front window  126  having first and second curved portions  180  and  181  with a first radius as well as third and fourth portions  182  and  184  with second larger radii. Radially extending surfaces  185  interconnect the adjacent curved portions. Key flange  166  is sized and shaped to clear front window  126  and enter cavity  108  at two angular orientations 180° apart. Key flange  166  also includes a front face  186  and a rear face  188 . Key flange  166  is spaced apart from circular base flange  162  by pilot portion  164 . Pilot portion  164  has an outer diameter smaller than circular base flange  162  and the curved portions of key flange  166 . Pilot portion  164  has a length slightly greater than the thickness of forward sidewall  100 . A chamfer (not shown) may be formed at the intersection of rear face  188  and portions  180 ,  181 ,  182  and  184 . This chamfer may be sized similarly to the chamfer formed on circular base flange  162 . Forward sidewall  100  may be more easily positioned between circular base flange  162  and key flange  166  if the chamfers are present. 
         [0032]    An aperture  192  extends through front retainer  128 . Aperture  192  includes a socket head clearance portion  194  having a first diameter, a main portion  196  having a second diameter, and a female locator portion  198  having a third diameter. Main portion  196  is sized to receive a body  200  of socket-head cap screw  156 . Socket head clearance portion  194  is sized to receive a head  202  of socket-head cap screw  156  such that an outer face  204  of head  202  sits flush with outer surface  170  of circular base flange  162 . Head  202  includes a hexagonally-shaped socket  206 . Female locator portion  198  is sized to receive a male locator portion  210  of rear retainer  134 . 
         [0033]    Rear retainer  134  is configured substantially similar to front retainer  128  and includes a circular base flange  212 , a pilot portion  214 , a key flange  216 , and cylindrically-shaped male locator portion  210 . Circular base flange  212  includes an outer surface  218 , an inner surface  220 , and a circumferential surface  222 . Inner surface  220  may also include ribs or protrusions (not shown) similar to ribs  176  or protrusions  178  to enhance torque/clamp load capacity on rearward sidewall  102  of compound link  30 . 
         [0034]    Key flange  216  is substantially similar in shape to rear window  132  having first and second curved portions  224  and  225  with a first radius as well as third and fourth curved portions  226  and  228  with second larger radii. Key flange  216  is sized and shaped to clear rear window  132  when properly aligned. Key flange  216  also includes a front face  230  and a rear face  232 . Pilot portion  214  extends between circular base flange  212  and key flange  216  having a length slightly greater than the thickness of rearward sidewall  102 . 
         [0035]    An aperture  236  extends through rear retainer  134 . Aperture  236  includes a hexagonally-shaped recess  238  and a main bore  240 . Main bore  240  includes internal threads  242  sized to engage external threads  244  of socket-head cap screw  156 . Recess  238  is sized to receive a hexagonally-shaped tool for applying counter torque to twist lock retainer assembly  130  while applying torque to socket-head cap screw  156 . 
         [0036]    It should be appreciated that the front retainer  128  and rear retainer  134  of twist lock retainer assembly  130  may be constructed from a number of materials. Specifically, it is contemplated that twist lock retainer assembly  130  includes mild steel either machined or formed by a powdered metal manufacturing method. 
         [0037]    Pivot arm assembly  44  includes a split bearing  290  located to rotatably support a journal  292  of a pivot arm  293  on twist lock retainer assembly  130 . Spit bearing  290  further includes a front half  294  and a rear half  296 . Front half  294  includes a body section  298  and a flange  300 . Rear half  296  also includes a body section  304  and a flange  306 . 
         [0038]    Pivot arm  293  further includes a cylindrical hub  310 , a first arm  312 , and a second arm  314 . Cylindrical hub  310  includes journal  292 , a front face  316 , a rear face  318 , and an outer face  320 . First arm  312  extends from cylindrical hub  310  and includes a tapered aperture  322 . Second arm  314  extends from cylindrical hub  310  and includes a tapered aperture  324 . 
         [0039]    Split bearing  290  functions as a multi-axial support member. Body sections  298  and  304  rotatably support journal  292  on cylindrical body  158  of twist lock retainer assembly  130  for rotation of pivot arm assembly  44  about axis X 1 . Flange  300  spaces apart front face  316  of cylindrical hub  310  and front face  186  of key flange  166  axially along X 1  and reacts a thrust load therebetween. Flange  306  spaces apart rear face  318  of cylindrical hub  310  from front face  230  axially along X 1  and reacts a thrust load therebetween. It should be appreciated that pivot arm  293  may be constructed from a number of materials. Specifically, it is contemplated that pivot arm  293  is composed of either forged or cast steel or a polymer composite over-molded on a stiff steel inner-structure. 
         [0040]    Pivot arm assembly  44  is placed in cavity  108  through either upper or lower window  122 ,  124  respectively. Pivot arm assembly  44  is positioned such that the center axis of cylindrical hub  310  is aligned with axis X 1 . While maintaining this position, front retainer  128  is rotated until the shape of key flange  166  is aligned with the outline of front window  126 . Key flange  166  is then inserted through front window  126  and split bearing  290 . Front retainer  128  is next rotated 90° such that forward sidewall  100  is captured between circular base flange  162  and key flange  166 . Movement of front retainer  128  relative to compound link  30  along axis X 1  is restricted. 
         [0041]    Rear retainer  134  is inserted through rear window  132  such that male locator portion  210  is received by female locator portion  198 . Rear retainer  134  is rotated to align key flange  216  with rear window  132 . Key flange  216  is then further translated within cavity  108 . Rear retainer  134  is next rotated 90° to capture rearward sidewall  102  between circular base flange  212  and key flange  216 . 
         [0042]    After front retainer  128  and rear retainer  134  are assembled together, socket-head cap screw  156  is inserted through front retainer  128  and threadingly engaged with rear retainer  134 . Socket-head cap screw  156  is tightened to lock the front and rear retainers  128 ,  134  together. After tightening, pivot arm  293  is able to rotate relative to twist lock retainer assembly  130  about axis X 1 . 
         [0043]    Twist lock retainer assembly  130  may also include an anti-rotational lock system  328  as depicted in  FIGS. 4 and 5 . Anti-rotational lock system  328  includes a first threaded aperture  330  extending through circular base flange  162 , a second threaded aperture  331  extending through forward side wall  100 , a third threaded aperture  332  extending through circular base flange  212 , a fourth aperture  333  extending through rearward sidewall  102 , and machine screws  334  and  336 . Machine screw  334  is threadingly engaged with at least one of apertures  330  and  331  and machine screw  336  is threadingly engaged with at least one of apertures  332  and  333  to prevent rotation of twist lock retainer assembly  130  about axis X 1 . 
         [0044]    Second link  56  is coupled to first arm  312  of pivot arm assembly  44  via a ball stud assembly  382  as shown in  FIG. 7 . Ball stud assembly  382  includes a ball stud  384 , a socket  386 , a cushion  388 , a seal  390  and a nut  392 . Ball stud  384  includes a tapered shank  394  in engagement with tapered aperture  322 . Nut  392  is threadingly engaged with a threaded portion  396  of shank  394  to mount ball stud  384  to first arm  312 . Cushion  388  is positioned within a pocket  398  formed within socket  386 . A ball portion  400  of ball stud  384  is also positioned within pocket  398  and supported by cushion  388 . A collar  402  couples first end  58  of second link  56  to ball stud assembly  382 . Seal  390  engages socket  386  and ball stud  384  to prevent ingress of contamination into pocket  398 . 
         [0045]    First link  46  is coupled to pivot arm assembly  44  via a ball stud assembly  382 ′. Ball stud assembly  382 ′ is substantially similar to ball stud assembly  382 . Accordingly, like elements are identified with similar reference numerals including a “prime” suffix. The interconnection of first link  46  with pivot arm assembly  44  is substantially similar to the interconnection of second link  56  with pivot arm assembly  44 . Accordingly, a repetitive description will not be provided. 
         [0046]    Referring to  FIGS. 8 and 9 , an alternate embodiment of the pivot assembly  44 ″ is illustrated. In this embodiment, the pivot pin is a pin  730  that is positioned within cavity  109  and coupled to forward sidewall  100  and rear sidewall  102 . Pin  730  is a substantially cylindrically shaped hollow member having first and second radial extending flanges  732 ,  734 . A first pilot portion  736  outwardly extends beyond first flange  732 . A second pilot portion  738  outwardly extends beyond second flange  734 . A central support or hub portion  740  extends between first flange  732  and second flange  734 . 
         [0047]    First pilot portion  736  extends through an aperture  742  that is formed in forward sidewall  100 . A land  744  of first flange  732  engages an inner surface  746  of first shell  110 . In similar fashion, second pilot portion  738  extends through an aperture that is  748  formed in rearward sidewall  102 . A land  750  engages an inner surface  752  of second shell  112 . First flange  732  and second flange  734  are spaced apart a predetermined distance to properly position first shell  110  relative to second shell  112  prior to welding the shells together. It should be appreciated that pin  730  may be constructed from a number of materials and may be coupled to compound link  30  using a variety of manufacturing techniques. Specifically, it is contemplated that pin  730  is an extruded member constructed from cold rolled steel. Pin  730  may alternatively be solid. 
         [0048]    Furthermore, it is contemplated that pin  730  is welded to rearward sidewall  102  prior to first shell  110  being welded to second shell  112 . After pin  730  has been fixed to rearward sidewall  102 , aperture  742  is aligned with first pilot portion  736  of hollow pin  730  such that a portion of hollow pin  730  extends therethrough. At this time, first shell  110  is welded to or otherwise fixed to second shell  112 . It is contemplated that first shell  110  and second shell  112  are steel members shaped by stamping, hydro-forming or another applicable metal forming process. 
         [0049]    Pivot arm assembly  44 ″ is rotatably supported on an outer surface  756  of pin  730  by a split bearing  758 . Spit bearing  758  includes an upper half  760  and a lower half  762 . Upper half  760  includes a body section  764  positioned between first and second end flanges  766 ,  768  respectively. Lower half  762  also includes a body section  770  as well as first and second end flanges  772 ,  774 . 
         [0050]    First half  50 ″ includes a body portion  780  having a mounting plane  782  and a journal  784 . First half  50 ″ also includes an arm portion  786  extending substantially perpendicular to mounting plane  782 . 
         [0051]    Second half  60 ″ is shaped substantially similarly to first half  50 ″ and includes a body portion  800 , a mounting plane  802 , a journal  804  and an arm portion  806 . 
         [0052]    First half  50 ″ and second half  60 ″ are coupled to one another by fasteners  814 . Upper half  760  engages journal  804  and rotatably supports first half  50 ″ while lower half  762  engages journal  784  and rotatably supports second half  60 ″ on pin  730 . It should be appreciated that pivot arm assembly  44 ″ is constructed in the multi-piece arrangement previously described to allow mounting of first half  50 ″ and second half  60 ″ to pin  730  after first shell  110  has been fixed to second shell  112 . Upper window  122  and lower window  124  are sized and positioned to allow upper split bearing half  760 , first half  50 ″, lower split bearing half  762  and second half  60 ″ to be positioned within cavity  109  by translating the components from positions outside of compound link  30 . Furthermore, windows  122  and  124  are sized to allow a tool to access fasteners  814  and apply torque thereto. 
         [0053]    At this level of assembly, pivot arm assembly  44 ″ is rotatably mounted to pin  730  and positioned such that first half  50 ″ and second half  60 ″ are longitudinally positioned between forward sidewall  100  and rearward sidewall  102 . In this manner, pivot arm assembly  44 ″ maximizes the available space within cavity  109  and does not protrude beyond the outer surface of either forward sidewall  100  or rearward sidewall  102 . First flange  732  and second flange  734  maintain the longitudinal position of pivot arm assembly  44 ″. 
         [0054]    First link  46  is coupled to arm portion  786  of first half  50 ″ via a ball stud assembly as previously described. Similarly, second link  56  is coupled to arm portion  806  of second half  60 ″ via a ball stud assembly. 
         [0055]    Furthermore, the foregoing discussion discloses and describes merely exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and Claims, that various changes, modifications and variations may be made therein without department from the scope of the invention as defined in the following Claims.