In a nutshell, all stairlifts work on the same principle whether curved or straight models. A Straight stairlift is always fitted to a straight staircase and its rail can vary in length dependant on how many steps the staircase has. A curved lift on the other hand is normally fitted to a staircase that has curves, flat landings between floors or over multiple levels. In both cases the rails are always attached to the staircase rather than the walls and the stairlift carriage is securely fitted to the rail using rollers and a geared drive cog thats permanently engaged to a geared rack on the rail.
99.9% of modern stairlifts run on a low DC voltage provided by internal batteries making them much safer than older 240v mains powered models that were fed by a cable to the carriage within a flexible protective ‘energy chain’. Being battery powered also means a modern stairlift will provide many journeys in the event of a power cut. A good quality pair of batteries can last 3 years or more with regular use while cheaper brands may only last a year or so. The old adage “You get what you pay for” rings very true here.
The basic operation of any stairlift hasn’t changed since its invention by entrepreneur C.C. Crispen in 1923. The rack and pinion design has worked so well for so many years that no manufacturer has felt the need for change, that said Mag-Lift or another form of modern propulsion might become a reality in the future.
Operating a stairlift is simple and all relies on movement of an up-and-down switch or joystick located on one or both armrests. While seated, the passenger operates the switch in the direction he/she wants to go and the lift will move in that direction. Sensors and electronics within the lift provide a soft-start so that the rider does not experience a jolt whether starting or stopping. These sensors also monitor the lifts position on the rail and automatically stop the lift at the end of its journey, even if the directional switch is still engaged.
Safety wise, all stairlifts are provided with ‘safety edges’ that detect any obstruction on or near the rail and stop the lift until the obstruction is removed. These spring loaded edges are normally fitted to the footrest and base of the carriage and can detect things such as kids toys to sleeping pets. A seat belt is always fitted and should be worn.
Can a stairlift ever lose control and speed down the rail? This is almost impossible due to a device called an OSG (Overspeed Governor) This clever piece of engineering is essentially a strong metal claw that centrifugally monitors the lifts speed. If the speed increases to anything higher than specified, the claw reacts by digging into the rail, bringing the stairlift to a brisk but safe halt. Once this has happened an engineer will need to be called to ascertain why the OSG activated. It could be a major fault or just simply a build up of gunge around the device caused by dust, oil and sometimes pet hair. This highlights the necessity to have a stairlift regularly serviced.
So in summary, a stairlift should not be feared. It uses many modern safety devices to ensure the passenger remains safe at all times. If annual servicing is also carried out, the risk of breakdown or accident is reduced even further. That said, we always recommend the passenger carries a phone at all times to alert neighbours or the emergency services in the event of an rare emergency, just in case.