Patent Abstract:
A motorcycle driver backrest has a pair of struts that support a backrest pad and are positioned on opposite sides of a motorcycle, where they are pivotally supported on brackets on the motorcycle. The struts have pivot assemblies that attach to the brackets that permit the backrest to be moved from a stopped working position for supporting a back of a motorcycle rider, to a forwardly folded position. The pivot assemblies are locked onto the brackets with latch dogs, and the latch dogs in turn are moveable between latched and unlatched positions with a hand actuator disc accessible from the exterior of the pivot assemblies. When the latch dog is in an unlatched position, the struts can be sprung apart for removal from the brackets.

Full Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to a backrest for a driver of a motorcycle which will pivot forwardly for clearance for a passenger to mount a passenger&#39;s seat, and which has pivot assemblies that can be adjusted to different longitudinal positions in a fore and aft direction.  
         [0002]     Backrests for motorcycle drivers have been utilized for increasing rider comfort. Some existing backrests permit adjusting the pivot mounting for the backrest in fore and aft direction along brackets on the sides of a motorcycle. However, the mounting is generally complex and requires tools for removing and replacing the pivot mounting. The typical prior art backrest is shown in U.S. Pat. No. 4,596,422.  
       SUMMARY OF THE INVENTION  
       [0003]     The present invention relates to a pivotal mounting for a motorcycle driver backrest that has a pair of pivot support assemblies that can be reliably locked into position on support brackets on a motorcycle, but also quickly removed and/or repositioned longitudinally when desired.  
         [0004]     The backrest engages a rearward mechanical stop in its usable position and it will pivot forwardly from its usable position to a second stopped position. The forward pivoting provides clearance for a passenger to mount the motorcycle.  
         [0005]     The pivot support assemblies have a quick release lock that locks the pivot supports for the backrest onto the support brackets using an irregularly shaped opening that insures each pivot support is properly oriented when installed and which holds the pivot supports stationary when the backrest is pivoted. The loads on the backrest are carried adequately. The pivot support assemblies are held with a quick release arrangement so the pivot support assemblies can be quickly removed or changed in position. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  fragmentarily shows a motorcycle with a backrest made according to the present invention installed thereon at the rear of the driver&#39;s seat;  
         [0007]      FIG. 2  is an enlarged side view of the right hand pivot support assembly shown in  FIG. 1 .  
         [0008]      FIG. 3  is a perspective view of the inside of the left hand pivot support assembly for the backrest shown in  FIG. 1 ;  
         [0009]      FIG. 4  is an exploded view of  FIG. 2  showing the parts used with the same pivot support shown in  FIG. 2 ;  
         [0010]      FIG. 5  is a view from an interior side of the left hand pivot support assembly of a motorcycle showing the mounting bracket used with the backrest of the present invention;  
         [0011]      FIG. 6  is an enlarged sectional view taken along  FIG. 6-6  in  FIG. 4 ;  
         [0012]      FIG. 7  is a fragmentary sectional view taken on line  7 - 7  in  FIG. 5 ; and  
         [0013]      FIG. 8  is a fragmentary sectional view taken on line  8 - 8  in  FIG. 7 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]     Referring to  FIG. 1 , a motorcycle is shown fragmentarily at  10 , and is of a conventional design. It includes a frame mounting a rider&#39;s seat  12  adjacent handlebars  14  and it has a passenger seat  16 . A trunk is shown generally at  18 . The frame of the motorcycle or other structural members extend upwardly along to the inside of the side panels  20  of the trunk.  
         [0015]     A driver&#39;s backrest mounting bracket  22  is secured to the panel  20  or to any suitable portion of the frame on each side of the motorcycle. A separate backrest mounting bracket  22  is mounted on each side of the motorcycle, and the mounting brackets  22  have forwardly projecting strap portions  24  onto which a backrest assembly  26  is mounted.  
         [0016]     The backrest assembly  26  includes a pair of support struts  30  that each have a pivot support assembly  32  at the lower end. The struts  30  support a backrest pad  33  in a suitable manner. Referring to  FIG. 5 , which is a view from the interior side of the left hand bracket strap  26  and pivot support assembly  32 , it can be seen that the forwardly extending strap  24  has three irregularly shaped, polygonal openings  26 A,  26 B, and  26 C formed therein. A separate pivot support assembly  32  supports each of the struts  30 . The brackets  22  are mounted on suitable structural elements of the motorcycle that have sufficient strength to support the backrest.  
         [0017]     The pivot support assemblies  32  are supported on the brackets  22  and are releasably mounted for quick adjustment along (fore and aft), or removal from, the brackets.  
         [0018]     Referring to  FIGS. 3-6  in particular, each pivot support assembly  32  includes a strut support disc  35  that has a lower flattened end  30 A of the strut  30  on each side of the motorcycle. The flattened ends  30 A are fixed (welded) to the strut support disc  35  ( FIG. 6 ). The flattened ends  30 A have holes that fit over a hub  35  at the center of the respective strut support disc and the flattened end extends across the diameter of the strut support disc. A cover housing  34  has stand off lugs  37  and rivets or fasteners  37 A are used to fix the housing  34  to the respective strut support disc  35 .  
         [0019]     The housing  34  on each side has an open neck  36  that receives the strut and a part annular flange  38  that extends around a central axis  41  of the support assembly  32  ( FIG. 4 ). A mounting pivot disc  42 , as shown in  FIG. 6 , has a sleeve  46  that extends to one side and which pivotally supports the hub  35 B of strut support disc  35  so the struts  30  can pivot between the desired portions.  
         [0020]     The pivot disc support lug  44  that is integral with the pivot disc  42  is formed on a side of the disc opposite from sleeve  46 . The lug  44  mounts the respective pivot disc  42  and the entire pivot support assembly  32  to the respective brackets  24 . A central bore  45  is formed in the sleeve  46  and the pivot disc  42 . The strut support discs  35  and housings  34  are thus pivotally mounted relative to the respective pivot disc  42  through the mounting of hub  35 B of disc  35  on sleeve  46 . The struts  30  pivot with the respective disc  35  on the respective sleeve  46 .  
         [0021]     A detent disc or ring  48  is slid onto the exterior of each sleeve  46  at the outer end of the sleeve and held in place with a pair of adjustable jam nuts  47 A and  47 B that thread onto the exterior of sleeve  46  on opposite sides of the disc  48 . The detent disc or ring  48  is thus held relative to the sleeve  46 . The jam nuts  47 A and  47 B can be reliably secured in place. Thus, the detent ring remains in a fixed position relative to the pivot disc  42 . The strut support disc  35  and the flat end portion  30 A of the respective strut are urged toward the radial flange surface of the respective pivot disc  42  with a pair of Belleville washers  49 A and  49 B that are between jam nut  47 B and the pivot disc  35 . The ______ washers  49 A and  49 B mounted as shown and are spring loaded. Adjusting jam nut  47 B changes the spring load so a desired resistance to pivoting of the backrest can be provided. A low friction material disc  51  is between the flattened end  30 A of the strut and the radial flange side surface of pivot disc  42 .  
         [0022]     The support lug  44  on the pivot disc  42  is of size and shape to extend through one of the openings  26 A,  26 B or  26 C of one of the brackets  22 , and the support lug  44  has an axially length substantially the same as, or slightly longer than, the thickness of the strap portion  24  of the respective mounting bracket  22 . A low friction material spacer  53  can be used to get the proper position of the outer end of lug  44 . The irregular (polygonal) shape of openings  26 A-C and the lug  44  are oriented so the pivot assemblies will always be at the proper rotational position when the lugs  44  are in place.  
         [0023]     A latch cam or dog  50  is non-rotatably held on a central bolt or pin  52  that passes through the bore  45  in the pivot disc  42 , in sleeve  46  and support lug  44 . The latch dog  50  slidably rests on the outer end surface of lug  44 . The other end of the bolt or pin  52  is non-rotatably secured to a hand actuator disc  56 . The lock dog  50  is threaded onto the bolt or pin at the desired location that permits rotating the latch dog. The latch dog is held in place on the central bolt or pin  52  with a suitable lock nut  54 . The hand actuator disc  56  has a hub  58  that is rotatably guided for rotation within an opening  60  in the wall  39  ( FIGS. 2 and 6 ). The hub  58  has three pockets shown at  62  that have springs in the pockets  64  which spring load detent balls  66  in an axial direction to engage and releasably seat in openings  68  in the detent disc or ring  48 .  
         [0024]     The strut support disc  35  supports the wall  39  of the housing  34 , as previously explained. The pivot disc  42  is secured to the bracket  22  and forms a stationary support. Each sleeve  46  rotatably supports the associated hub  35 B, the strut support disc  35 , the respective strut  30  and housing  34  when in a working assembly as shown in cross-section in  FIG. 6 . The pivot disc  42  periphery fits within the flange  38  of the housing  34 .  
         [0025]     The pivot discs  42  are mounted in the brackets  22 , on the sides of the motorcycle. The struts  30 , strut support discs  35 , and housings  34  will pivot about the axis  41  relative to the pivot discs  42 , and thus will pivot relative to the brackets  22  and the motorcycle.  
         [0026]     It has been explained that the detent disc  48  is secured to the pivot disc  42 , so detent disc or ring  48  and the hand actuator disc remain with the disc  42  when the backrest is pivoted and do not pivot or rotate. The hand actuator disc  56 , which mounts to screw  52  and controls the rotational position of the lock dog or cam  50 , will remain in its position relative to the pivot disc  42  until the hand actuator disc is rotated with manual force to move from its detented position.  
         [0027]     The pivot disc  42  has pre-shaped or wedge shaped fixed stop lugs  55 A and  55 B projecting from the side surface opposite from the support lug  44 . As can be seen in  FIG. 7 , in one relative pivotal position of the struts  30  and the disc and housing, one edge of each of the flattened portions  30 A of the struts  30  will engage a respective first stop lug  55 A.  FIG. 7  shows one of the struts  30  in its usable or working position with the strut extending generally uprightly. The struts  30 , support discs  35 , and the housing  34  can be rotated in direction as indicated by the arrow  57 , so that the second edges of the flattened portions  30 A of the struts  30  will engage a respective second stop lug  55 B that is shown in dotted lines in  FIG. 7  as well. The struts  30  can pivot forwardly and lower the backrest down toward the driver&#39;s seat. The pivot amount permitted is about 90 degrees, between the stops, but the backrest may not have to be pivoted that much to provide passenger clearance.  FIG. 8  shows the stop face of lug  55 A.  
         [0028]     The pivot disc  42  is fixed relative to the brackets  22  so the stops  55 A and  55 B are also fixed relative to the motorcycle. The stops limit the pivoting movement of the rider backrest assembly.  
         [0029]     The latch dog  50  is held securely on the pin or screw  52  so that it will rotate positively when the hand actuator disc  56  is rotated relative to the pivot disc  42 . The detent balls  66  will retract against the springs  64  so that the rotation of the latch dog  50  can take place for removal of the struts  30  from the brackets  22 . The hand actuator disc  56  will not rotate unintentionally.  
         [0030]     The latch dog  50  will move between a solid line position shown in  FIG. 4  where the lug  44  can be withdrawn from the opening  26 B and the pivot disc  42 , the housing  34  and the respective strut  30  can be removed from the bracket  22 , and either moved to a different opening in the strap portion  24  at each side of the motorcycle, or left off, if the backrest is not needed or desired.  
         [0031]     When the latch dog  50  is moved by turning the hand actuator disc  56  substantially 60 degrees, the latch dog  50  moves to its dotted line position in  FIG. 4  and will lock the hub  44  in the aperture on the strap  24  so that the pivot assembly cannot be removed from the bracket strap  24 . The locked position of the hand actuator disc is the detented positions, so the latch dog  50  will securely hold the struts and the backrest in place. The locked position of the hand actuator disc  56  is shown in  FIG. 2  where an indicator arrow  70  on one of three raised ribs  72  aligns with a mark  74  on the housing  34 .  
         [0032]     Struts  30  can be flexed outwardly far enough so that the respective support lug  44  and the latch dog  54  will clear the brackets  22  so that the backrest can be removed.  
         [0033]     The latch dog  50  is operated by the hand actuator disc  56  for locking the pivot disc in position on the bracket mounted on the motorcycle. The latch dog  50  can be moved to a position where it will pass through the opening for the support lug  44  on the pivot disc. The backrest can be removed and replaced, or repositioned without special tools, and it can be done quickly, efficiently and positively. The backrest will remain locked in place in use because the detenting of the hand actuator disc  56  in its locked position.  
         [0034]     When the backrest is pivoted forwardly, the hand actuator disc remains in its locking position, since the support disc  35  moves, but the pivot disc  42  detent ring  48 , the hand actuator disc  56  and the latch cam or dog  50  do not rotate and remain stationary.  
         [0035]     Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Technology Classification (CPC): 1