Top-load zip line trolleys with variable speed control

Abstract

A top-load trolley with speed control system is disclosed. The trolley has a housing of metal plates with a series of fixed and movable parts mounted between. A number of rollers are moveably mounted in-line within the housing such that they may ride atop of a zip line and support the weight of the trolley and a passenger. An additional roller is placed in opposition to the load-bearing rollers, arranged to contact the zip line along its underside. Thus, at least three rollers may be configured to produce an adjustable amount of friction on the zip line, thereby providing a more controlled speed down a zip line course. Additionally, an emergency brake mechanism that may be used in conjunction with the top-load trolley with speed control system is disclosed.

What is claimed is: 
     
         1 . A trolley, comprising:
 a housing;   a first roller and a second roller connected to the housing and spaced from one another, the first and second rollers being adapted to rotate;   a lower roller mounted movably within the housing and placed in opposition to the first and second rollers, the lower roller being movable in a direction that takes it closer to or farther away from the first and second rollers.   
     
     
         2 . The trolley of  claim 1 , further comprising a channel provided along a top surface of the trolley, the channel configured to allow the first and second rollers to be seated atop a zip line with the zip line within the trolley. 
     
     
         3 . The trolley of  claim 1 , further comprising a channel formable along a top surface of the trolley, the channel comprising an opening to allow the first and second rollers to be seated atop a zip line with the zip line passing through the trolley. 
     
     
         4 . The trolley of  claim 1 , the lower roller further comprising a rotatable pivoting plate and a linkage wherein said lower roller is configured to adjust the speed of the trolley. 
     
     
         5 . The trolley of  claim 1 , wherein the lower roller promotes braking of the trolley when the lower roller is moved in a direction that is closer to the first and second rollers. 
     
     
         6 . The trolley of  claim 1 , further comprising a clutch bearing coupled to the trolley and a third roller, wherein the clutch bearing is configured to prevent the trolley from rolling backwards. 
     
     
         7 . The trolley of  claim 3 , the channel further comprising a gate biased toward the closed position. 
     
     
         8 . The trolley of  claim 1 , further comprising a capture barb configured to engage a cavity of a brake disposed on the zip line. 
     
     
         9 . The trolley of  claim 1 , the zip line further comprising a brake disposed on the zip line to receive and capture the trolley. 
     
     
         10 . The trolley of  claim 8 , the capture barb further comprises magnets to bias the position of the capture barb. 
     
     
         11 . The trolley of  claim 2 , further comprising a magnetic rope connected to a brake and the zip line, wherein said magnetic rope is ferromagnetically attracted to the zip line. 
     
     
         12 . A trolley, comprising:
 a housing;   a first roller and a second roller connected to the housing and spaced from one another, the first and second rollers being adapted to rotate;   a lower roller mounted within the housing and placed in opposition to the first and second rollers, the first and second rollers being movable in a direction that takes the first and second rollers closer to or farther away from the lower roller.   
     
     
         13 . The trolley of  claim 12 , further comprising a channel formable along a top surface of the trolley, the channel configured to allow the first and second rollers to be seated atop a zip line with the zip line passing through the trolley. 
     
     
         14 . The trolley of  claim 12 , further comprising a switch configured to adjust the speed of the trolley by altering a position of the first and second rollers relative to the lower roller. 
     
     
         15 . The trolley of  claim 12 , further comprising a clutch bearing coupled to the trolley and a third roller, wherein the clutch bearing is configured to prevent the trolley from rolling backwards. 
     
     
         16 . The trolley of  claim 12 , further comprising a capture barb configured to engage a cavity of a brake disposed on the zip line. 
     
     
         17 . The system of  claim 12 , further comprising a tether coupled to the trolley. 
     
     
         18 . The system of  claim 12 , further comprising a brake configured to stop the trolley before it reaches a support. 
     
     
         19 . The trolley of  claim 12 , further comprising a handle coupled to the trolley. 
     
     
         20 . A method of controlling speed of a trolley, comprising:
 advancing a trolley adapted to ride on a zip line along a specified direction of travel;   engaging, with a zip line, a first roller, a second roller, and a third roller connected to a housing, said first roller, said second roller, and said third roller spaced from one another; and   adjusting the speed of the trolley by moving a position of said first, second, and third rollers relative to the zip line.