Abstract:
A cable riding transporter having one or more drive sheaves in rolling contact with the upper side of a suspended cable and including a motor operatively engaging at least one of the drive sheaves for propelling the retriever along the cable and including a control for operating the motor and its direction of rotation and mechanism to interconnect the transporter with a load, such as a zip line trolley.

Description:
[0001]    The present invention relates generally to transport apparatus and system that operates on a suspended cable. The present invention is particularly adapted for use on a recreational zip line to retrieve trolleys that have run to the lower end of the line. 
       BACKGROUND 
       [0002]    A zip line basically consists of a trolley movably suspended on a cable that is erected over an inclined area. It is designed to enable a user to be propelled by gravity to travel from the top to the bottom of the inclined cable by holding on to, or attaching to, the freely moving trolley. Zip-lines come in many forms, most often used as a means of entertainment. They may be short and low, intended for child&#39;s play as found on some playgrounds. Longer and higher rides have become popular amusement rides and vacation activities. After the rider reaches the bottom end of the zip line cable the trolley must be returned to the top. The trolley return has been accomplished by several means. In simple low to the ground installations the return can be done by simply pushing the trolley back to the top of the cable on foot. The return has also been carried out with a line leading from the trolley to the uphill end of the line. In other installations the trolley is removed from the zip line and transported in some manor back to the top of the ride. Another method of return includes the passenger, as shown in U.S. Patent Application publication No. 2014/0182477. 
         [0003]    The primary object of the present invention is to overcome the necessity for additional personnel, vehicles and time to carry out the cumbersome task of returning the zip line trolley to the higher elevation starting point. 
         [0004]    A further object of the invention is to provide a simple transporter apparatus that can tow or push a cable suspended load carrier. 
         [0005]    Other and further features and advantages of the present invention will be seen from an examination of the following specification, drawings and claims. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a diagrammatic side view of the zip line in which a rider is carried by a seat hanging from a cable engaging trolley from an upper station to a lower station. 
           [0007]      FIG. 2  is a diagrammatic side view of the zip line of  FIG. 1  there the trolley retriever of the present invention follows the trolley to the lower station and attaches to the trolley. 
           [0008]      FIG. 3   FIG. 2  is a diagrammatic side view of the zip line of  FIG. 1  where the batter powered retriever of the present invention has towed the trolley back to the higher station. 
           [0009]      FIG. 4  is a fragmentary side view of the zip line trolley and the retriever of the present invention. 
           [0010]      FIG. 5  is an enlarged fragmentary side view of the retriever of the present invention. 
           [0011]      FIG. 6  is a cross sectional view taken along lines  6 - 6  of  FIG. 5 . 
           [0012]      FIG. 7  is a side view of a second embodiment of the retriever where the retriever has a single sheave running on the supporting cable. 
           [0013]      FIG. 8  is a cross sectional view of the second embodiment taken along lines  8 - 8  in  FIG. 7 . 
       
    
    
     SUMMARY OF THE INVENTION 
       [0014]    The transporter, or trolley retriever, of the present invention comprises a least one sheave that is in rolling contact with a supporting suspended cable. The at least one sheave is operatively interconnected to a battery powered motor which turns the at least one sheave and drives the retriever along the cable to either position the transporter on the cable or to tow another cable suspended apparatus. 
       DETAILED DESCRIPTION 
       [0015]    The transporter  2  of the present invention is diagrammatically shown in its role as a zip line trolley retriever in  FIGS. 1-3 . A zip line cable  4  is suspended between a high elevation support station  6  and a lower elevation support station  8 . A rolling trolley  10 , from which hangs a passenger support  12 , is supported by the suspended cable  4 . In a well known manner the passenger rides the trolley  10  and its attached platform  12  to the lower elevation station where the passenger disembarks from the platform, as shown in  FIG. 1 . When activated by a control mechanism, the retriever  2  is motor driven down the suspended cable  4  to a point proximate the trolley  10  where is connects to the trolley, as shown in  FIG. 2 . When activated by the control mechanism, the retriever, with the trolley in tow, is motor driven up the cable to the higher elevation station  6  where the trolley is disconnected and made ready for the next zip line decent, as shown in  FIG. 3 . 
         [0016]    The retriever  2  comprises a body  15  that comprises side members that depend over each side of the zip line cable  4 . Located in the interior of the retriever body  15 , a pair of spaced apart sheaves  18  and  20  is disposed in rolling engagement with the upper side of the cable  4 . The sheaves rotate on axles  22  and  24 , which are attached at their respective ends to the depending sides of the body. A reversible DC motor  30  within the body  15  is provided with an output gear  32 , which operates an endless loop drive belt  34  that engages gears  36  and  38  that are fixed to the respective sheaves  18  and  20  and which rotate on axles  22  and  24 . Although a traditional drive belt is shown as the operative connection between the DC motor and the sheaves a gearing connection can also be used. 
         [0017]    A hook  40  is carried by the body and is adapted to connect with a receiving pin  42  on the trolley. 
         [0018]    The body  15  also carries a battery (not shown in the drawings) for powering the DC motor. 
         [0019]    Preferably, the DC motor  30  is controlled by a traditional wireless controller  45  however; other known control options may be used. 
         [0020]    As shown in  FIG. 7 , a second embodiment of the zip line retriever  2 ″ comprises a single drive sheave  60  mounted in rolling engagement with the top side of the suspended cable  4 . The sheave rotates on an axle  62 . The distal end  64  of a depending lever  66  is pivotally attached to the sheave&#39;s axle  62 . The proximal end  71  of the lever pivotally carries one end of an elongated hook  75 , which is provided for connection to a load, such as a zip line trolley, that is to be towed by the retriever  2 ″. The pivotal mounting of the hook allows it to be bumped by the load that will be towed by the retriever. The load&#39;s impact force on the hook causes it to pivot around point  74  to a position where the hook can engage a connecting loop on the load. Biasing springs  77  and  78  cause the hook to return to its center position once the hook is engaged with the load. 
         [0021]    Beneath a mounting collar  79  and attached to the lever  66  is a laterally disposed floor  88  that carries a battery  91 , a motor  93  and motor control apparatus  94 . The traditionally geared output of the motor is operatively connected to the axle  62  for turning the sheave  60  and propelling the retriever  2 ″. Although a geared motor is the preferred form of a drive system, a motor and drive belt combination could also be used. 
         [0022]    Intermediate the distal and proximal ends of the lever  66  and below the suspended cable, a lateral extension  76  of a collar  79 , that surrounds and is attached to the lever, provides a mounting platform  80  for the center of a flat cantilever spring  82  that extends laterally of the lever in a direction that is in alignment with and below the suspended cable  4 . At the terminal ends of the cantilever spring there is mounted a pair of tensioner pulleys  84  and  86 , the peripheral grooves of which engage the underside of the suspended cable  4  at a distance from the sheave  60 . 
         [0023]    The function of the tensioner pulleys is two-fold. First, assume that the retriever  2 ″ is programmed to travel in direction  90  and tow a load with the hook  75 , creating force R that tends to pivot the lever  66  clockwise around its axis  62 . The force moment that is created is R×r 2 , the distance between the longitudinal center of the hook  75  and the center of rotation of the lever, the sheave axle  62 . In order for the system to remain in equilibrium the sum of the force moments in the system must be zero, that is, the opposing force moments must be equal. That equilibrium is created be the force moment F×r 1  where F is the force exerted by the tensioner pulley  84  against the cable  4  and r 1  is the distance between the spring mounting platform  80  and the center of the sheave axle  62 . 
         [0024]    The second function of the tensioner pulley is to increase the force of the drive sheave on the suspended cable  4  as the load force R increases, thus increasing the traction between the sheave and the cable. This reaction is seen by examining the forces present in the system as the force R increases. Statically, in summing the existing vertical forces, the weight of the system W is exerted against the suspended cable  4  through the drive sheave  60 , which is in contact with the cable  4 . The cable reacts with an opposing force N, supplemented by upward forces F 1 +F 2 , provided by the cantilever spring  82  through the tensioner pulleys  84  and  86 . Thus, W=N+F 1 +F 2 . Dynamically, when the retriever is towing a load that creates a force R on the lever  66  reference can again be made to the sum of the moments equation, F 1 r 1 =Rr 2 . Therefore, when R becomes a value or increases, F 1  increases since both of the r values remain constant. Accordingly, when F 1  increases, W also increases, since W=N+F 1 +F 2 , thus increasing the traction between the sheave  60  and the cable  4  and thereby increasing the driving force D.