Anti-Roll Back Assembly with Linear Magnetic Positioning

Abstract

An anti-roll back (ARB) assembly for use with vehicles that ride on a track, which has inclined portions that include a set of ARB or lift pins. The assembly includes a linear magnet assembly positioned along the track in the ARB portion, and this assembly includes spaced apart magnet arrays that define a slot or elongated magnetic force zone. The ARB assembly includes an ARB element with a body pivotally supported on a vehicle frame and further includes an electrically conductive reaction plate supported on the vehicle frame, and the plate passes through the magnet assembly slot when the vehicle travels on the track. The reaction plate is connected to the ARB body to pivot it in response to displacement of the reaction plate in response to magnetic forces to rotate it up into a suspended position in which the ARB body is spaced apart from the ARB pins.

1 . An anti-roll back (ARB) assembly for use with vehicles that ride on a track including an ARB portion adapted with a plurality of ARB pins, comprising:
 a linear magnet assembly positioned along the track in the ARB portion, the linear magnet assembly comprising a pair of magnet arrays spaced apart to define a slot extending the length of the linear magnet assembly;   an ARB element having a body pivotally supported on a frame of one of the vehicles; and   an electrically conductive reaction plate supported on the frame of the vehicle and positioned such that the reaction plate passes through the slot when the vehicle travels on the track over the ARB portion, wherein the reaction plate is connected to the ARB element and the ARB body pivots in response to movement of the reaction plate to position the ARB body relative to the frame of the vehicle.   
     
     
         2 . The assembly of  claim 1 , further comprising a pivot pin supported on a frame of the vehicle, wherein the ARB body is rigidly attached to the pivot pin at a first location and the reaction plate is rigidly attached to the pivot pin at a second location spaced apart from the first location. 
     
     
         3 . The assembly of  claim 1 , wherein when the vehicle travels over the ARB portion in a first direction a force is applied to the reaction plate in a second direction opposite the first direction. 
     
     
         4 . The assembly of  claim 3 , wherein when the vehicle travels at a velocity exceeding a minimum speed in the first direction the force has a magnitude gnat enough to displace the reaction plate a predefined amount causing the ARB body to pivot into a suspended position in which the ARB body is spaced apart from the ARB pins. 
     
     
         5 . The assembly of  claim 1 , wherein when the vehicle is spaced apart from the linear magnet assembly and when the vehicle travels in the second direction the ARB body is rotated downward to be positioned in a down position in which the ARB body can engage the ARB pins. 
     
     
         6 . The assembly of  claim 1 , wherein when the one of the vehicles supporting the ARB element travels at a velocity less than a minimum speed in the first direction the ARB body pivots into a lowered position or is maintained in the lowered position. 
     
     
         7 . The assembly of  claim 1 , wherein the reaction plate has a ratio of volume to area of between about 0.35 and about 0.5. 
     
     
         8 . The assembly of  claim 1 , wherein the reaction plate has a body having a prismatic sector shape. 
     
     
         9 . An anti-roll back assembly, comprising:
 an anti-roll back (ARB) member including a body with a first end and a second end with an ARB pin receiving surface, wherein the ARB body is pivotally mounted to a frame of a vehicle;   a fin with a planar body formed at least partially of electrically conductive material, wherein the fin extends outward from the vehicle frame and is linked to the ARB body, whereby the ARB body is pivoted between a first position with the first end abutting the vehicle frame and a second position with the second end abutting the vehicle frame in response to displacement of the fin;   an eddy current assembly positioned along a length of track for the vehicle, wherein the eddy current assembly includes a gap provided between linear arrays of permanent magnets for receiving the fin when the vehicle travels over the length of the track; and   a pivot pin pivotally supported on the vehicle frame, wherein the ARB body and the fin are rigidly attached to the pivot pin.   
     
     
         10 . The assembly of  claim 9 , wherein a plurality of ARB pins are provided along the length of the track and wherein the ARB body engages at least one of the ARB pins with the second end when pivoted into the second position and the second end of the ARB body is spaced apart from adjacent ones of the ARB pins when the ARB body is pivoted into the second position. 
     
     
         11 . The assembly of  claim 9 , wherein the permanent magnets are arranged within the arrays to generate a magnetic zone in the gap that creates an eddy current in the fin body when the fin passes through the gap at a velocity exceeding a predefined minimum velocity. 
     
     
         12 . The assembly of  claim 11 , wherein, in response to the fin passing through the gap, a force is applied to the fin body in a direction opposite to a direction of travel of the fin body, whereby the fin is displaced to move the connected ARB body to the first position or to the second position. 
     
     
         13 . The assembly of  claim 9 , further comprising a resilient return member connecting the fin to the vehicle frame that applies a force on the fin to be displaced to urge the ARB body toward the first position. 
     
     
         14 . The assembly of  claim 9 , wherein the in has a ratio of volume to area of between about 0.35 and about 0.5. 
     
     
         15 . The assembly of  claim 9 , wherein the fin comprises a trapezoidal prism. 
     
     
         16 . An amusement park ride, comprising:
 a vehicle track with an inclined portion including a plurality of stops;   a vehicle adapted for traveling on the vehicle track and including a structural portion adjacent the vehicle track;   an anti-roll back pawl pivotally attached to the structural portion of the vehicle;   a reaction blade protruding outward from the structural portion of the vehicle, the reaction blade having a planar body formed at least partially from electrically conductive material, wherein the reaction blade is linked to the anti-roll back pawl; and   positioned along the inclined portion of the vehicle track, a linear magnet assembly comprising two spaced apart, linear arrays of permanent magnets defining an elongated gap between the arrays, wherein the reaction blade extends into the gap between the arrays when the vehicle travels over the inclined portion,   wherein the planar body of the reaction blade protrudes downward from the vehicle further than the anti-roll back pawl.   
     
     
         17 . The ride of  claim 16 , further including a pivot pin pivotally supported on the structural portion of the vehicle and wherein the anti-roll back pawl is attached to the pivot pin to rotate with the pivot pin and the reaction blade is rigidly attached to the pivot pin, whereby the pivot pin is rotationally displaced with movement of the reaction plate. 
     
     
         18 . The ride of  claim 16 , wherein a force is imparted upon the reaction blade when the vehicle travels over the inclined portion and wherein the force is opposite in direction to a direction of travel of the vehicle. 
     
     
         19 . The ride of  claim 18 , wherein the anti-roll back pawl is positionable in a first position in which the anti-roll back pawl contacts the stops when the vehicle travels over the inclined portion and is positionable in a second position in which the anti-roll back pawl is spaced apart from proximal ones of the stops. 
     
     
         20 . The ride of  claim 19 , wherein when the vehicle travels over the inclined portion a force is applied on the reaction blade causing a magnitude of displacement and wherein the reaction blade is linked to the anti-roll back pawl to translate the displacement of the reaction blade into a movement of the anti-roll back pawl from the first to the second position or from the second to the first position.