Abstract:
The present invention discloses a zipline trolley comprising of two substantially flat side flanges arranged in a parallel configuration, a substantially flat front face attached perpendicularly to the front edges of the side flanges, and a substantially flat back face attached perpendicularly to the rear edges of the side flanges. There are also provided two axles for bearing wheels and four lines for attaching the side flanges to the two spreaders. One set of two lines is attached to the bottom of each of the side flanges. The lines are connected to two spreaders, which are attached to the ends of a handlebar.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 60/975,942, filed Sep. 28, 2007, the contents of which are hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to zipline trolleys. 
       BACKGROUND OF THE INVENTION 
       [0003]    Zipline systems typically comprise a trolley that rolls along a suspended length of cable. A conventional trolley is constructed from a cylindrical aluminum frame enclosing two wheels. These wheels roll along the top of the cable. A handlebar is suspended from the bottom of the aluminum frame by four lines. One or more slings may also be used to attach the trolley to the user. The front of the trolley comprises a pair of vertical rings extending away from the trolley. The rings are used to engage the braking mechanism at the end of the cable length. 
         [0004]    The conventional trolley is bulky and heavy, making it difficult to transport it from one end of the cable to the other. The design of the trolley also makes it difficult to remove and replace the wheels, lines, and slings, which is periodically necessary to allow for replacement due to wear and tear. 
       SUMMARY OF THE INVENTION 
       [0005]    In one aspect of the present invention, a zipline trolley comprises a substantially flat first side flange and a substantially flat second side flanged arranged in a parallel configuration, with a substantially flat front face attached perpendicularly to the front edges of the first and second side flanges and a substantially flat back face attached perpendicularly to the rear edges of the first and second side flanges. Two axles are provided for bearing wheels, with the axles arranged in a spaced arrangement between the first and second side flanges. There are four lines comprised of a first two lines, with one end of each of the first two lines attached to the first side flange, and a second two lines, with one end of each of the second two lines attached to the second side flange. There are also provided a first spreader, which is attached to the other end of each of the first two lines, and a second spreader, which is attached to the other end of each of the second two lines. The ends of a handlebar are attached to the two spreaders. 
         [0006]    In another aspect of the invention, the four lines are attached to the two side flanges using a swage eye toggle assembly. 
         [0007]    In yet another aspect of the invention, the spreaders are weldedly connected to the ends of the handlebar. 
         [0008]    In another aspect of the invention, the side flanges each comprise one or more holes that are adapted to allow for gripping the zipline trolley. 
         [0009]    The foregoing was intended as a broad summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the preferred embodiment and to the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0010]    The invention will be described by reference to the detailed description of the preferred embodiment and to the drawings thereof in which: 
           [0011]      FIG. 1  is a perspective view of the trolley according to the preferred embodiment of the invention; 
           [0012]      FIG. 2  is a bottom view of the upper frame of the trolley according to the preferred embodiment of the invention; 
           [0013]      FIG. 3  is a side view of the upper frame of the trolley according to the preferred embodiment of the invention; and 
           [0014]      FIG. 4  is a front view of the upper frame of the trolley according to the preferred embodiment of the invention, with the wheels and zipline cable shown. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0015]    The present invention comprises a trolley that is lighter and more compact than the conventional trolley. This trolley also allows for the easier removal and replacement of the wheels, lines, and slings. 
         [0016]    Referring to  FIG. 1 , the trolley of the present invention comprises an upper frame  1  with a substantially flat left flange  10  and a substantially flat right flange  20  arranged parallel with each other. The front edge of left flange  10  and the front edge of right flange  20  are rigidly attached to a substantially flat front face  30 , while the rear edge of left flange  10  and the rear edge of right flange  20  are rigidly attached to a substantially flat back face  40 . Preferably, the front edge of left flange  10  forms a right angle with flat front face  30 , and the front edge of right flange  20  forms a right angle with flat front face  30 . Similarly, the rear edge of left flange  10  preferably forms a right angle with flat back face  40 , and the rear edge of right flange  20  forms a right angle with flat back face  40 . As a result, left flange  10 , right flange  20 , front face  30 , and back face  40  form a generally box-like configuration. 
         [0017]    Front face  30  comprises a front slit  50 , and back face  40  comprises a back slit  55 . Front slit  50  extends vertically from approximately midway along the bottom edge of front face  30  to approximately the center of front face  30 . Similarly, back slit  55  extends vertically from approximately midway along the bottom edge of back face  40  to approximately the center of back face  40 . Front slit  50  and back slit  55  are of sufficient width to allow front face  30  and back face  40 , respectively, to accommodate the diameter of a zipline cable  2 . Preferably, the tops of front slit  50  and back slit  55  are semi-circular in shape. Referring to  FIG. 3 , front slit  50  and back slit  55  are horizontally aligned with each other to allow for zipline cable  2  to run through front face  30  and back face  40 . Left flange  10  and right flange  20  are spaced sufficiently apart so that zipline cable  2  can pass between them. 
         [0018]    Preferably, one edge of a substantially flat member  15  is rigidly attached at a right angle to the inner surface of left flange  10 . The opposite edge of substantially flat member  15  is rigidly attached at a right angle to the inner surface of right flange  20 . Substantially flat member  15  therefore extends between left flange  10  and right flange  20  and provides strength and rigidity to the structure of upper frame  1 . Referring to  FIG. 2 , preferably, a first corner member  11  is attached perpendicularly to the outside of the joint between left flange  10  and front face  30 . Preferably, a second corner member  12  is attached perpendicularly to the outside of the joint between right flange  20  and front face  30 . Preferably, a third corner member  13  is attached perpendicularly to the outside of the joint between left flange  10  and back face  40 . Preferably, a fourth corner member  14  is attached perpendicularly to the outside of the joint between right flange  20  and back face  40 . corner members  11 ,  12 ,  13 ,  14  are attached perpendicularly to the outside of the joints between the left flange  10  and the front face  30 , between the left flange  10  and the back face  40 , between the right flange  20  and the front face  30 , and between the right flange  20  and the back face  40 . Corner members  11 ,  12 ,  13 ,  14  add rigidity to the box-like configuration of the upper frame  1 . Preferably, the left flange  10 , the right flange  20 , the front face  30 , the rear face  40 , the substantially flat member  15 , and the corner members  11 ,  12 ,  13 ,  14  are made of an aluminum alloy, to reduce the overall weight of the trolley. 
         [0019]    Along the top edge of left flange  10  are a left front protrusion  65  and a left rear protrusion  75 , spaced apart from each other. Similarly, along the top edge of right flange  20  are a right front protrusion  66  and a right rear protrusion  76 , again spaced apart from each other. Left front protrusion  65  comprises a left front axle hole  60 , while left rear protrusion  75  comprises a left rear axle hole  70 . Similarly, right front protrusion  66  comprises a right front axle hole  61 , while right rear protrusion  76  comprises a right rear axle hole  71 . Left front axle hole  60  and right front axle hole  61  are aligned with each other, and left rear axle hole  70  and right rear axle hole  71  are aligned with each other. This allows for a front axle  160  to span left front axle hole  60  and right front axle hole  61  and a rear axle  161  to span left rear axle hole  70  and right rear axle hole  71 . 
         [0020]    Referring to  FIG. 4 , a front axle wheel  67  is attached to front axle  160  and sits in between left flange  10  and right flange  20 . A rear axle wheel  68  is attached to rear axle  161  and sits in between left flange  10  and right flange  20 . Front axle wheel  67  and rear axle wheel  68  ride on top of the suspended zipline cable  2 . Front axle wheel  67  is attached to front axle  160  using a front nut and bolt connection  162 , and rear axle wheel  68  is attached to rear axle  161  using a rear nut and bolt connection  163 . Preferably, front and rear nut and bolt connections  162 ,  163  comprise stainless steel bolts and Nylock nuts to allow for easy removal of axle wheels  67 ,  68  for replacement. 
         [0021]    The tracks of axle wheels  67 ,  68  are preferably grooved to allow for better tracking of axle wheels  67 ,  68  with the suspended zipline cable  2 . Preferably, axle wheels  67 ,  68  are made of high-density urethane. The bottom of upper frame  1  is uncovered, to allow for easy placement of axle wheels  67 ,  68  of the trolley on top of zipline cable  2 . Except for substantially flat member  15 , the top of the trolley is uncovered, to reduce the overall weight of the trolley. 
         [0022]    A left front projecting flange  85  and a left rear projecting flange  80  project from the bottom edge of left flange  10  and are spaced apart from each other. Similarly, a right front projecting flange  86  and a right rear projecting flange  81  project from the bottom edge of right flange  20  and are spaced apart from each other. Preferably, left front projecting flange  85  is aligned with right front projecting flange  86 , and left rear projecting flange  80  is aligned with right rear projecting flange  81 . Left front and left rear projecting flanges  85 ,  80  are at an angle from left flange  10  such that they project away from left flange  10 . Similarly, right front and right rear projecting flanges  86 ,  81  are at an angle from the right flange  20  such that they project away from the right flange  20 . Preferably, the projecting flanges  80 ,  81 ,  85 ,  86  project at an angle of approximately 25° away from vertical. Left front projecting flange  85  comprises a left front hole  90 , left rear projecting flange  80  comprises a left rear hole  91 , right front projecting flange  86  comprises a right front hole  92 , and right rear projecting flange  81  comprises a right rear hole  93 . 
         [0023]    A lower frame  3  of the trolley comprises a first line  100 , a second line  101 , a third line  102 , a fourth line  103 , a left spreader  110 , a right spreader  115 , and a handlebar  130 . The lines  100 ,  101 ,  102 ,  103  hang below upper frame  1 . First line  100  is attached at one end to left front hole  90  and at the other end to a left front spreader hole  120  on left spreader  110 . Second line  101  is attached at one end to left rear hole  91  and at the other end to a left rear spreader hole  121  on left spreader  110 . Third line  102  is attached at one end to right front hole  92  and at the other end to a right front spreader hole  122  on right spreader  110 . Fourth line  103  is attached at one end to right rear hold  93  and at the other end to a right rear spreader hole  123  on right spreader  110 . 
         [0024]    Preferably, the lines  100 ,  101 ,  102 ,  103  are attached to their respective holes using a connection found typically in lifeline connections, such as a swage eye toggle assembly. The use of such connections increases the strength of the connections compared with those of conventional crimped connections. Handlebar  130  spans left spreader  110  and right spreader  115 . Preferably, handlebar  130  and left and right spreaders  110 ,  115  are made from aluminum. The left end of handlebar  130  is welded to left spreader  110  while the right end of handlebar  130  is welded to right spreader  115 . By having the ends of handlebar  130  welded to left and right spreaders  110 ,  115 , the overall weight of the trolley is reduced, as bolts or other connecting members are not required. 
         [0025]    Left spreader  110  comprises a left sling hole  150 , and right spreader  115  comprises a right sling hole  151 . A sling is attached to left sling hole  150  and right sling hole  151  using a choker knot. The sling is removably attached to a modified paragliding harness that is worn by the zipline rider. The attachment of the harness to the sling ensures that the rider remains connected to the trolley at all times while it is in motion. 
         [0026]    The angulation of lines  100 ,  101 ,  102 ,  103  with respect to vertical is determined in part by the length of lines  100 ,  101 ,  102 ,  103  and the width of handlebar  130 . In one embodiment, the length of lines  100 ,  101 ,  102 ,  103  is approximately 16.5 inches (from centre of respective spreader holes to center of respective front holes and rear holes), and the length of handlebar  130  is approximately 18 inches. In this embodiment, the horizontal distance between left flange  10  and right flange  20  is approximately 1.5 inches. These dimensions comprise only one possible example; other dimensions may be used without departing from the principles of the invention. This angulation limits the degree of “swing-up” by left and right spreaders  110 ,  115  as the trolley travels along the length of zipline cable  2 . 
         [0027]    The axle wheels  67 ,  68  of the trolley allow it to travel smoothly over the suspended zipline cable  2 . In order to stop the trolley (i.e. when it reaches the end of zipline cable  2 ), a catch block braking system may be used. The catch block braking system comprises two buckles that snap around and grip the two side edges of flat front face  30  when the trolley impacts the buckles. A spring attached to the buckles along the longitudinal direction of zipline cable  2  compresses and absorbs the impact of the trolley as it impacts on the buckles. The braking system prevents the spring from decompressing, and so the trolley is not propelled back. 
         [0028]    Preferably, the top and bottom edges of front face  30  are substantially flat, while the side edges are rounded and protrude out from the side edges. The protruding side edges are gripped by the buckles of the catch block braking system. Preferably, the outer rims of the side edges of front face  30  are rounded or flared to allow the buckles to slide over and grip the sides easier. To disengage the trolley from the buckles of the catch block braking system, the frame of the trolley is rotated 90° about the longitudinal axis of zipline cable  2  (so that the substantially flat edges of front face  30  formerly on the top and bottom are now on the sides). Since the buckles are fixed to the braking system and cannot rotate, the buckles disengage from the trolley because they can no longer grip onto the substantially flat edges of front face  30 . Upper frame  1  of the trolley can then be removed from zipline cable  2 . 
         [0029]    In another embodiment of the invention, in order to remove the trolley from the cable, handlebar  130  can be separated at the middle. Once handlebar  130  has been separated, the entire trolley can then be removed by detaching upper frame  1  from zipline cable  2  and by swinging the lines on one side of the trolley over zipline cable  2 . 
         [0030]    Preferably, left flange  10  and right flange  20  each comprise one or more holes  140  to allow for upper frame  1  of the trolley to be easily grasped by a hand. 
         [0031]    Preferably, the trolley is of a symmetrical shape such that the front and rear ends of the trolley are mirror images of each other. If the front and rear ends of the trolley are mirror images of each other, then the trolley can be oriented in either direction and still allow the braking system to work as intended. The left and right sides of the trolley are preferably also mirror images of each other as well. 
         [0032]    The connections for the axles  160 ,  161  and the lines  100 ,  101 ,  102 ,  103  are designed for easy disconnection. This allows the axles  160 ,  161  (and axle wheels  67 ,  68 ) and the lines  100 ,  101 ,  102 ,  103 ,  104  to be easily removed for inspection and/or replacement. 
         [0033]    It will be appreciated by those skilled in the art that the preferred and alternative embodiments have been described in some detail but that certain modifications may be practiced without departing from the principles of the invention.