Abstract:
A tow ball coupling and holder member suitable for towing a wheelie bin or transporting a bicycle. The tow ball coupling has a mechanism which is quick and simple to attach and remove without great physical effort or mechanical knowledge. The tow ball coupling includes a tow ball housing and a releasable tow ball catch arranged to allow the housing to admit the ball without manual operation of the catch.

Description:
FIELD OF INVENTION 
       [0001]    The present invention relates to couplings attachable to tow balls on vehicles for transporting various items such as wheelie bins, bicycles and the like and to holders for such items. 
       BACKGROUND OF THE INVENTION 
       [0002]    There are a number of items that are either too heavy or unwieldy lift by hand or, for other reasons, need to be transported by vehicle. It may not be desirable or possible to place such items inside a vehicle, such as an ordinary family car for example. Such items include wheelie bins, bicycles, light weight off road trailers such as those used for garden waste and the like. 
         [0003]    Wheelie bins may be heavy and it may be difficult to wheel them to the road or other rubbish collection areas particularly where long or steep driveways need to be traversed or where residents needing to move the bins are elderly. 
         [0004]    There have been a number of proposals for towing devices for wheelie bins by vehicles. For example, Australian innovation patent 2007100062 in the name of Amaze Promotions Pty Ltd describes a device consisting of an arm which has a hook member at one end that is placed through the handle of a wheelie bin and an aperture at the other end which attaches to a spike on the toe bar. When used with this device the wheelie bin must be loaded very close to the ground making it difficult to control as the bin may tip over. 
         [0005]    Another proposal is that of Australian patent application 16343/97 in the name of Kaden which discloses a wheelie bin towbar hitch comprising two arms disposed at right angles with spring-loaded pins for engaging the wheelie bin and the toe ball. Again this appears to suffer from similar problems in that the bin would have to be lowered to the ground and may tip over. Further the operation of the spring-loaded pins may be difficult for elderly people with arthritic hands. 
         [0006]    Other proposals such as U.S. Pat. No. 3,376,051 in the name of Bacher and U.S. Pat. No. 7,735,850 in the name of Curran relate to trailer hitches and ball mounts which require the operation of cumbersome levers or fiddly pins. 
         [0007]    The above references to and descriptions of prior proposals or products are not intended to be, and are not to be construed as, statements or admissions of common general knowledge in the art. 
       SUMMARY OF THE INVENTION 
       [0008]    In a first aspect the present invention provides a tow ball coupling suitable for use with a tow ball mounted on a vehicle, said coupling adapted to allow a vehicle to transport and/or tow at least one item, said coupling comprising: a) a suitable ball housing with an open end such that the coupling may be placed above the ball and lowered onto the ball, said housing being of a suitable size to restrict lateral movement of the ball within the housing; b) a releasable ball catch adjacent said open end of the ball housing which catch is movable between a ball retaining condition which retains the ball within the housing by limiting the vertical movement of the ball and a ball releasing condition; and c) a holder member for holding at least one item; d) wherein the housing and the catch are arranged such that relative movement of the coupling towards the ball displaces the catch to admit the ball to the housing without manual operation of the catch. 
         [0009]    The present inventor set out to provide a tow ball coupling with a mechanism which is quick and simple to attach and remove without great physical effort or mechanical knowledge. Thus the tow ball coupling would be suitable for use by aged people or others who are not physically strong. 
         [0010]    The term “items” refers to wheelie bins, bicycles and other domestic items which it may be desirable to transport on the exterior of a vehicle. 
         [0011]    The term “a suitable ball housing” refers to an enclosure of suitable size and material to accommodate a tow ball of a vehicle. Preferably the ball housing is a cylinder made of aluminium, thermoplastics or other suitable material. 
         [0012]    The term “ball catch” refers to a catch which is able to limit relative movement of the coupling and the ball by engaging the ball in cooperation with the ball housing. Preferably the ball catch will be in the form of a pawl. Even more preferably the pawl is biased for engagement with the tow ball. Still more preferably the pawl may be released by an associated manually operable lever. Yet more preferably the lever is biased such that the pawl remains in a ball retaining condition until the lever is operated. 
         [0013]    The term “a ball retaining condition” refers to the ball being captured or confined within the housing. 
         [0014]    The term “a ball releasing condition” refers to the housing being able to be removed from the ball (and vice versa). 
         [0015]    The relative movement of the coupling towards the ball is facilitated by the weight of the coupling itself in combination with the holder member. The weight of the coupling and holder member exert downward force which causes the ball catch to admit the ball to the housing automatically with minimal manual input other than placing the coupling above the tow ball and releasing it. 
         [0016]    The term “a holder member” refers to a member for holding or attaching the item to the coupling. This may be a conventional holder for holding a bicycle crossbar such as two plates with suitable concavities which can be screwed together or the novel holder developed by the present inventor and described below. 
         [0017]    In another separate development the present invention provides a holder for supporting an elongated portion of an item such as a handle of a wheelie bin or a portion of a bicycle frame which item is to be carried or towed by a tow bar of a vehicle, said holder comprising: a suitable body mounted with a rotating closure member said body having an open condition and a closed condition wherein in said open condition said elongate portion of the item can be placed in said holder body and in a closed condition the elongate portion of the item is retained within the holder body wherein said holder is suitable for mounting on a vehicle via a tow ball coupling. 
         [0018]    The term “suitable body” refers to the body being of an appropriate size and shape to be able to contain the elongate portion of the item. 
         [0019]    Preferably the body is semicircular in cross section and defines a channel. Similarly, preferably the rotatable closure member is also semicircular in cross section and is slidably mounted on the body such that in a closed condition they form a cylindrical enclosure over the wheelie bin handle, for example. Depending on the item to be transported or towed, the long axis of the cylindrical enclosure can be parallel to the ground (for towing wheelie bin) or perpendicular to the ground for carrying a bicycle by its seat post. 
         [0020]    In a particularly preferred aspect the invention provides a tow bracket which incorporates the tow ball coupling and holder separated by a riser. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    The invention will now be described with reference to the following non limiting illustrative drawings. 
           [0022]      FIG. 1  is a schematic partial side view of a car with a tow bracket incorporating the tow ball coupling and holder towing a wheelie bin. 
           [0023]      FIG. 2  is a rear perspective view of the tow bracket. 
           [0024]      FIG. 3 a    is a side view of a longitudinal section of the ball housing with the tow ball inside. 
           [0025]      FIG. 3 b    is a side view of a longitudinal section of the ball housing with a tow ball entering the housing. 
           [0026]      FIG. 3 c    is a top view schematic of the ball housing showing line A-A representing the section illustrated in  FIGS. 3 a    and  3   b.    
           [0027]      FIG. 4  is a rear 3-D perspective view of the holder in a closed condition. 
           [0028]      FIG. 5 a    is a front 3-D perspective view of the holder in an open condition. 
           [0029]      FIG. 5 b    is a rear 3-D perspective view of the holder in an open condition. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0030]      FIG. 1  shows vehicle  10  towing a single wheelie bin  50  with tow bracket  300  mounted on tow ball  15 . For reasons of clarity tow ball  15  is shown in  FIG. 1  with a smaller diameter in relation to the housing which is more accurately represented in  FIGS. 3 a  and 3 b    described below. 
         [0031]    As seen in  FIG. 2  tow bracket  300  incorporates both developments made by the present inventor: tow ball coupling  100  at one end and holder  200  at the other end separated by riser  160 . 
         [0032]    While in a preferred embodiment tow bracket  300  is provided as described it will be appreciated that tow ball coupling  100  and holder  200  may be provided independently and combined with other holders and tow ball couplings accordingly. In tow bracket  300  shown in  FIG. 2  tow ball coupling  100  and riser  160  are provided by the same tubular member  170  which is capped by holder  200 . It should be understood that different constructions/assembly configurations are also contemplated. 
         [0033]    Where tow bracket  300  is produced to tow wheelie bin  50 , riser  160  is of sufficient height so that it only needs to be tipped slightly to be attached to tow bracket  300 . Riser  160  may be made of different heights/lengths to accommodate other items such as bicycles. While the drawings show only a single item being towed it is also contemplated that two or more risers  160 , sufficiently spaced may be provided in combination with tow ball coupling  100 . 
         [0034]    Tow ball coupling  100  provided at foot of tow bracket  300  comprises ball housing  110  defined by cylindrical sidewall  112  with open end  115  leading into housing interior  118 . Although a tube with a cylindrical sidewall is illustrated, it is possible that straight sidewalls either to form a square or triangle in cross section could be used provided the ball housing is of the appropriate size to snugly fit tow ball  15 . 
         [0035]    Self-locking latching assembly unit  150  adjacent open end  115  is made up of releasable ball catch  120 , plates  130 , lever  140 , hairpin spring  128  and torsion spring  148 . 
         [0036]    Releasable ball catch  120  in the form of pawl  125  is pivotally mounted on a pair of parallel plates  130  fixed on side wall  112 . Pawl  125  is made of aluminium and is basically a distorted “L” shape with main body  125   a  and tongue  125   b . Tongue  125   b  extends into interior  118  via aperture  112  a and is biased in a positive locking position by hairpin spring  128 . Hairpin spring  128  is basically V-shaped in profile with a short arm  128   a  and a long arm  128   b . Short arm  128   a  is mounted adjacent the vertex of pawl  125  and long arm  128   b  is freestanding. Arms  128   a  and  128   b  of hairpin spring are biased for compression with long arm  128   b  resting over part of aperture  112   a  and against adjacent sidewall  112  when pawl  125  is in a ball retaining condition. 
         [0037]    Lever  140  with thumb catch  145  at one end and arm  142  at the other end are an integral unit pivotally mounted above pawl  125  on plates  130 . Lever  140  is bolted to plates  130  together with associated torsion spring  148  to bias it in position. Lever arm  142  extends between arms  128   a  and  128   b  of hairpin spring  128 . Lever arm  142  cooperates with pawl  125  in its ball retaining condition by sitting alongside long arm  128   b  of hairpin spring  128 . When pivoted into the ball release position as seen in  FIG. 3 b    lever arm  142  pushes on short arm  128   a . Long arm  128   b  also cooperates by pressing on lever arm  142  to pivot tongue  125   b  out of housing interior  118  thus allowing pawl  125  to disengage with tow ball  15 . This enables coupling  100  to be lifted off. 
         [0038]    It will be noted that in the ball retaining condition tongue  125   b  just needs to engage tow ball  15  anywhere below the centreline (between the widest part of the tow ball and including its neck). 
         [0039]    Pawl  125  is mounted so that it is pushed by tow ball  15  and pivots out of the way to allow tow ball  15  to pass into ball housing  110  via aperture  112   a . The weight of the coupling and any riser or other attachment allows the coupling to be simply dropped onto ball  15  with no precise guidance needed. Pawl  125  is automatically pivoted out of housing interior  118  when coupling  100  is dropped onto ball  15 . In addition, because of its bias pawl  125  immediately assumes a ball retaining condition which locks ball  15  in place. 
         [0040]    Lever  140  is activated to achieve a ball releasing condition. Lever  140  operates to release pawl  125  by pressing thumb catch  145  towards tubular member  170  (described below) causing pawl  125  to pivot and withdrawing tongue  125   b  from ball housing  110 . The automatic locking and the requirement for positive manual operation of the lever to release the coupling is an important feature of the invention. 
         [0041]    Riser  160  in the form of tubular member  170  is made out of suitably strong aluminium, the lower end of which forms ball housing  110   
         [0042]    Holder  200  is made of injection moulded thermoplastic material and comprises capped sleeve  210  and holder body  220 . 
         [0043]    Capped sleeve  210  has open end  215  and is of suitable size and shape for fitting to riser  160  and secured by gluing or other suitable fixing means. 
         [0044]    Holder body  220  is cylinder-like in a closed condition and disposed at right angles to sleeve  210 . Holder body  220  comprises mouth  230  moulded in one piece and rotatable closure means  240  in the form of sliding gate  245 . Sliding gate  245  is moulded in two pieces. 
         [0045]    Mouth  230  is semicircular in cross section and comprises a cavity or channel with an interval or opening defined by slot  237  (see  FIG. 5 a   ). Mouth  230  also comprises stepped ends  235 . Stepped ends  235  are for mounting sliding gate  245 . 
         [0046]    Sliding gate  245  is similar in cross section to mouth  230  and is cylinder-like in shape with opening  247  along its length and annular recesses  248  at each end. Sliding gate  245  has handle  250  located opposite opening  247 . 
         [0047]    Sliding gate  245  is mounted onto mouth  230  by stepped ends  235  which are dovetailed into annular recesses  248 . This dovetailing arrangement allows sliding gate  245  to be rotated in mouth  230 . When handle  250  is rotated downward towards tubular member  170 , holder  200  is in an open condition. In this condition a wheelie bin handle or other elongate member can be placed into sliding gate  245  and handle  250  can be rotated back again to put holder  200  in a closed position. Optionally a locking means (not shown) may be included to retain holder  200  in a closed position. 
       REFERENCE NUMBER LIST 
       [0048]      
         [0000]    
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                 Reference Numeral 
                 Feature/part 
               
               
                   
                   
               
             
             
               
                   
                  10 
                 Vehicle 
               
               
                   
                  15 
                 Tow ball 
               
               
                   
                  50 
                 Wheelie bin 
               
               
                   
                 100 
                 Tow ball coupling 
               
               
                   
                 110 
                 ball housing 
               
               
                   
                 112 
                 Sidewall 
               
               
                   
                 112a 
                 Aperture in sidewall 
               
               
                   
                 115 
                 Open end in ball housing 
               
               
                   
                 118 
                 Housing interior 
               
               
                   
                 120 
                 Releasable ball catch 
               
               
                   
                 125 
                 Pawl 
               
               
                   
                 125a 
                 Main body of pawl 
               
               
                   
                 125b 
                 tongue on pawl 
               
               
                   
                 128 
                 Hairpin spring 
               
               
                   
                 128a 
                 Short arm of hairpin spring 
               
               
                   
                 128b 
                 Long arm of hairpin spring 
               
               
                   
                 130 
                 Parallel mounting plates 
               
               
                   
                 140 
                 Lever 
               
               
                   
                 142 
                 Arm of Lever 
               
               
                   
                 145 
                 Thumb catch on Lever 
               
               
                   
                 148 
                 Torsion spring 
               
               
                   
                 150 
                 Self-locking Latching assembly unit 
               
               
                   
                 160 
                 Riser 
               
               
                   
                 170 
                 Tubular member 
               
               
                   
                 200 
                 Holder 
               
               
                   
                 210 
                 Capped sleeve 
               
               
                   
                 220 
                 Holder body 
               
               
                   
                 230 
                 Mouth of holder body 
               
               
                   
                 235a and b 
                 Stepped ends of mouth 
               
               
                   
                 237 
                 Slot on mouth 
               
               
                   
                 240 
                 Rotatable closure 
               
               
                   
                 245 
                 Sliding gate 
               
               
                   
                 247 
                 Opening on sliding gate 
               
               
                   
                 248 
                 Annular recesses on sliding gate 
               
               
                   
                 250 
                 Handle 
               
               
                   
                 300 
                 Tow bracket 
               
               
                   
                   
               
             
          
         
       
     
         [0049]    From the foregoing, it will be observed that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiment illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims. 
         [0050]    Throughout this specification and the claims that follow, unless the context requires otherwise the words “comprise,” “comprises,” “comprising” will be understood to mean the inclusion of the stated integer, step or group of integers or steps but not the exclusion of any of other integer, step or group of integers or steps.