In Beijing, China, plans are underway to build the Great Wheel of China. The giant Ferris Wheel should be completed later this year. It will stand 680 ft high (208 m), which is more than 130 ft (40 m) taller than the current highest wheel in Singapore. The wheel will have 48 air-conditioned carriages that will each hold 40 passengers, for a total capacity of 1,920 passengers. On clear days passengers will have a view stretching all the way to the Great Wall of China. The wheel should make 750,000 rotations over a period of 50 years so only products that are designed to deliver extended service life were considered, according to the manufacturer.
For China’s great ferris wheel, linear actuators open the doors and electromagnetic clutches control the yaw of each of the 48 observation carriages.
Linear actuators open the doors and electromagnetic clutches control the yaw of each of the 48 observation carriages.
The linear actuators function as a secondary lock to prevent the door from opening during rotation. Each actuator includes an adjustable end limit switch, end stroke signal, specific stud, nut and washer arrangements, a manual release lever, and extruded aluminum tube bodies to avoid corrosion and reduce weight.
Electromagnetic tooth clutches keep each carriage axis vertical as the wheel rotates in the strong winds present at such a height, preventing the carriages from swaying so that passengers will not suffer from motion sickness throughout the 20-minute ride.
The tooth clutches offer high torque in areas limited to size, thus the relatively small clutches stabilize the cabins. Each clutch has a flexible coupling that compensates for misalignments and eases mounting. In the event of the transmission locking on the wheel, the clutch will be disengaged to leave the cabin free. A hand release lever also allows for manual disengagement.
Warner Electric, Altra Industrial Motion
Filed Under: Actuators, Linear motion • slides, Motion control • motor controls