The present invention relates to a remotely controlled motor driven apparatus for retrieving a gravitationally propelled load carrying conveyance that travels on and is supported by a sloping cable.
The broad nature of the present invention is personified in the present day popular zip line systems that embody a gravitationally propelled cable-supported trolley for transporting a rider from the top elevated end of a cable to the bottom lower end of the cable. In connection with a zip line, the retrieving apparatus retrieves the trolley from the lower end of the cable by pushing it back to the top end of the zip line cable immediately upon its discharge of the rider.
Prior art methods and apparatus for retrieving a zip line passenger-carrying trolley from the bottom end of the zip line cable back to the top end have involved towing the trolley back to the top end station with a rope, cable or motorized device, the latter of which is described in U.S. Pat. No. 9,579,678 to Ronald Chasteen. Such a towing device works well but is burdened with time constraints, especially with long length zip lines having high volume traffic. When the passenger trolley reaches the bottom end of the zip line the towing retriever must traverse the same line itself and then tow the trolley back to the high end of the line to position it for another trip down the line.
The primary object of the present invention is to have a trolley retriever in position at the bottom of the line to begin pushing the trolley back to the top of the line immediately on the disembarking of the passenger from the trolley. After retrieving the trolley to the top end of the line, the pushing retriever is returned to the bottom at a high speed while the next zip line passenger is being readied for the decent.
The zip line system to which the present invention applies includes upper and lower supports for an elongated zip line cable on which a gravitationally propelled passenger-carrying trolley travels from the upper to the lower end of the zip line. The trolley retriever of the present invention is positioned at the lower end of the zip line cable between the trolley and the lower support. The retriever is adapted to travel on the zip line cable propelled by a reversible remotely controlled motor that drives the retriever to push the trolley up the zip line cable and then propel the retriever back down the cable to position it for retrieving a subsequent trolley. Preferably, the retriever includes a body having idler pulleys that support the retriever on the cable and includes one or more drive wheels that contact the underside of the cable and which are driven, through appropriate linkage, by the remotely controlled reversible motor mounted within the housing.
While one embodiment of the invention is described herein as a retriever for a zip line trolley, the scope of the invention includes using the retriever on a suspended cable to drive any kind of cargo or load that is also suspended on and movable on the same cable.
Projecting from the right side of the flat body plate 22 is a lateral extension 40 which carries an enclosure 42 that houses an electric drive motor 50. The output shaft of the motor terminates in a pinion gear 53 that meshes with a drive gear 55. The output shaft of the drive gear 55 interacts with a transmission 57 whose output is connected to a coupler 60 whose output shaft 61 is supported by a pillow block bearing 63 and which output shaft becomes the axle of the drive wheel having a tire 70. The upper portion of the drive wheel and tire 70 protrudes through the rectangular cut out 27 so that its peripheral surface of the tire makes tangential contact with the underside of the cable 5. To achieve maximum driving contact between the tire 70 and the cable 5 the tire is filled with foam. The pressure of the cable on the foam filled tire causes the tire surface to be depressed at the point of cable contact so that the cable runs through a trough in the tire surface.
A pair of idler pulleys 81 and 83 are disposed on either side of the drive wheel and tire 70. Each of the pulleys contacts the top side of the cable 5 to apply a spring driven downward force on the cable 5 to create driving friction between the cable and the drive wheel and tire 70. The central shaft of each of the idler pulleys is supported by arms 86 that are rotatably mounted on studs 87 that are mounted on and protruding from the turned up plate edge 29. Also carried by the studs 87 are torsion springs 89 each of which has one end 91 fixed to the upturned edge 29 and the other end laying against a respective supporting arm 86 in order to bias the related idler pulley down against the cable 5.
A container 95 depending from the plate 22 carries traditional electronic components to receive from a remote location signals that operate the drive motor and control its speed in a traditional manner.