Borrowing technology from the automotive industry, flexible shafts are increasingly playing an important role in railways, especially high speed trains, for operating many crucial systems. These trains travel at speeds of more than 220 miles per hour.
With the world’s railway business expected to flourish, especially the high-speed rail systems, flexible shaft applications that can extend to all areas of the railway system: electric seat adjustment mechanism, air conditioning controls and back-up operation system of the pantograph.
While diesel-electric locomotives are predominant in the USA, in many other places in the world, trains draw electricity from overhead power lines via a roof-mounted pantograph. Under normal conditions, these pantographs are raised and lowered electrically, powered by the train-internal battery system. Inherent with all electric systems is a potential for failures and locomotives, and therefore have purely mechanical emergency operating systems. However, in order to operate this system, the train operator has to exit the train.
Locomotive manufacturers and designers are now coming up with a new mechanical override system, which makes use of manually operated flex shafts. This allows the train operator to adjust the height of the pantograph from inside the train thereby eliminating the need to exit. In addition to added comfort and reducing the risk for the operator when working from the outside of the train, the inside cab operation gives the ability to adjust the height of the pantograph while the train is in motion, this is needed to compensate variation in the height of the power line above ground, allowing the locomotive to operate under external power.
A flexible shaft consists of layers of wires wrapped around a central core. Depending on the construction, completely different shaft characteristics can be achieved, allowing maximum flexibility, torsional stiffness or minimum deflection, for example, meeting the exact needs of the application. Its main advantage lies in the simple design that provides reliable performance and low cost.
SUHNER’s flexible shafts are being used on high-speed trains in China that travel at speeds of more than 220 miles per hour. When travelling at ultra-high speeds like these, light conditions for the train conductor can change very quickly; therefore, a quick reacting, electrically-powered interior shading systems keeping the glare out of the conductor’s eyes is critical to safety.
Borrowing technology from the automotive industry, SUHNER is using two synchronised, permanently sealed, SSB-5 flexible shaft assemblies to bring the rotary motion to the device lowering and raising the shade cloth. This design allows mounting the electro motors out of sight at a convenient location. Flexible shaft assemblies don’t require maintenance, they are also pre-lubricated to ensure long life operation.
Despite the rapid development that we have seen of electronic/electrical, pneumatic and hydraulic transmission power systems, flexible shafts are widely used in many mechanical devices. The main advantage lies in the simple design that provides reliable performance and low cost. A flexible shaft consists of layers of wires wrapped around a central core wire. Depending on the construction, completely different shaft characteristics can be achieved, allowing maximum flexibility, torsional stiffness or minimum deflection. For example, meeting the exact needs of the application.
Courtesy: SUHNER India Private Limited, Bangalore. Tel: 080-27831108. Email: transmission.in@suhner.com
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