Zipwire trolley braking
A zipwire trolley having a plurality of zipwire engaging rollers, a swivelable brake block assembly adjacent to one of the rollers, the brake block having a zipwire-engaging cam by which the roller can be at least partially lifted off the zipwire when the trolley is moving in a rearward direction, the cam having a pair of tapered sidewalls tending to pinch respectively opposite sides of the upper part of the zipwire as the brake block progressively rotates when the trolley is moving in a rearward direction, thereby preventing or inhibiting further rearward movement of the trolley.
1. A zipwire trolley having a plurality of zipwire engaging rollers, a swivelable brake block adjacent to one of the rollers, the brake block having a zipwire-engaging cam by which the roller can be at least partially lifted off the zipwire when the trolley is moving in a rearward direction, the cam having a pair of tapered sidewalls tending to pinch respectively opposite sides of the upper part of the zipwire as the brake block progressively rotates when the trolley is moving in a rearward direction, thereby preventing or inhibiting further rearward movement of the trolley.
2. A zipwire trolley according to claim 1 wherein the brake block is adjustable as to width.
3. A zipwire trolley according to claim 2 wherein the brake block is adjustable by being split in a plane coincident with the major axis of the zipwire when the brake block is mounted thereon.
4. A zipwire trolley according to claim 1 wherein the brake block is co-operable with a swivelable lever arm by which upon anti-clockwise rotation of the lever arm the brake block mechanism is disengaged, thereby allowing the zipwire trolley to be moved along the zipwire in a rearward direction relative to a normal forward direction.
5. A zipwire trolley according to claim 4 wherein clockwise movement of the lever arm also disengages the brake block by causing the brake block to swivel away from the zipwire.
6. A swivellable zipwire trolley brake block assembly having a cam with tapered sidewalls tending to pinch respectively opposite sides of the upper part of the zipwire as the brake block progressively rotates when the trolley is moving in a rearward direction, thereby preventing or inhibiting further rearward movement of the trolley.
7. The brake block assembly of claim 6 wherein the brake block is adjustable as to width.
8. The brake block assembly of claim 7 wherein the assembly is split in a plane coincident with the major axis of the zipwire when the brake block is mounted thereon.
9. A brake block assembly according to claim 6 wherein the brake block is co-operable with a swivelable lever arm by which upon anti-clockwise rotation of the lever arm the brake block mechanism is disengaged, thereby allowing the zipwire trolley to be moved along the zipwire in a rearward direction relative to a normal forward direction of travel.
10. A brake block assembly according to claim 9 wherein clockwise movement of the lever arm also disengages the brake block from the zipwire by causing the bracke block to swivel away from the zipwire.