Patent Application
20160075343
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.
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'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.
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.
A further object of the invention is to provide a simple transporter apparatus that can tow or push a cable suspended load carrier.
Other and further features and advantages of the present invention will be seen from an examination of the following specification, drawings and claims.
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.
The transporter 2 of the present invention is diagrammatically shown in its role as a zip line trolley retriever in
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.
A hook 40 is carried by the body and is adapted to connect with a receiving pin 42 on the trolley.
The body 15 also carries a battery (not shown in the drawings) for powering the DC motor.
Preferably, the DC motor 30 is controlled by a traditional wireless controller 45 however; other known control options may be used.
As shown in
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.
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.
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×r2, 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×r1 where F is the force exerted by the tensioner pulley 84 against the cable 4 and r1 is the distance between the spring mounting platform 80 and the center of the sheave axle 62.
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 F1+F2, provided by the cantilever spring 82 through the tensioner pulleys 84 and 86. Thus, W=N+F1+F2. 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, F1r1=Rr2. Therefore, when R becomes a value or increases, F1 increases since both of the r values remain constant. Accordingly, when F1 increases, W also increases, since W=N+F1+F2, thus increasing the traction between the sheave 60 and the cable 4 and thereby increasing the driving force D.
