英设计出可"拐弯"的电梯

100多年来，电梯一直都是沿直线向上或者向下运行的。现在这种局面要改变了。英国伦敦城市大学的杰克·列维教授发明出了可以“拐弯”的电梯，这种以其发明者命名的“列维梯”可随意沿弯道运行。因为“列维梯”上有弧度的楼梯很像回转寿司餐厅的传送带，所以人们也叫它“寿司梯”。跟传统的电梯相比，“寿司梯”有以下几点优势：传统的手扶电梯需要两个单独的环形传动带，不仅造价高，而且传动带通常只有一半在使用。而“寿司梯”只需要一个环形传动带，成本低廉且便于清理；另外，传统电梯台阶和墙壁之间有缝隙，总会有东西或者是人不小心被卡住，而“寿司梯”则不存在这种问题。该电梯的设计已经在英国、欧洲、美国和中国申请了专利，预计2012年年中我们就可以在公共建筑和商场里见到这种电梯了。

For more than 100 years the escalator has traditionally travelled either up or down and in a straight line.

But all that is set to change thanks to a revolutionary new design that is being hailed as the future of escalator travel.

The Levytator, named after its inventor Jack Levy, professor of mechanical engineering at City University in London, is the world's first escalator capable of following free-form curves.

It is already being nicknamed the 'Sushi-lator' because of its curved modules, which resemble the conveyor belts used to deliver food in trendy Japanese restaurants.

These curved steps allow it to twist, bend and snake around corners in a continuous loop, all with passengers on board.

All of which means architects can create escalators in any shape they want, whether as a conveyor belt around a department store, a ride around a theme park or, more simply, placed on top of an existing staircase.

The popularity of the imaginative design is clear. A YouTube video showing how the Levytator works has gone viral with more than 230,000 hits since it was first posted in September.

The inspiration for the free-form escalator's design came to Professor Levy while travelling around the London Underground. 'I wondered why the escalators had to be straight,' he told The Independent. 'Sometimes it's really convenient to go round a corner.'

The traditional escalator works by turning the steps upside down and looping them underneath the staircase to take them back to the start. Half the steps are therefore hidden away and never 'in use'.

Furthermore, the 'up' and 'down' escalators require two separate loops, each costing around £100,000 each.

The Levytator, on the other hand, has one single loop, making it a cheaper proposition because fewer steps are required.

This works because when they reach the top, the steps disappear under the floor and then reappear for the downward journey.

The design also means repairs can be carried out from above, avoiding the weeks and months it currently takes to fix faulty escalators.

Professor Levy said: 'Traditional escalators developed topsy-turvy, but we're starting with a clean sheet of paper.'

Safety is another factor that is likely to appeal to architects the world over - the Levytator has no gap between the stairs and the walls where people and things have for years become jammed.

Professor Levy said: 'Worldwide, there are 10,000 accidents on escalators every year, including several deaths. On two occasions I've seen people piling up at the bottom of an escalator and had to press the emergency stop button.'

His design has already been patented in the UK, Europe, the US and China and Levytators could be cropping up in public buildings and shopping centres by mid-2012.

The first escalator in Britain was installed in Harrods department store in Knightsbridge, London, in 1898, two years after it was invented in the US.