A Chinese firm which makes self-balancing two wheeled scooter-like vehicles has bought its US rival Segway, it said Wednesday -- only months after being accused of copying its designs.

Segway, founded by the inventor of the quirky vehicles, last year sought US government action against Ninebot and several other Chinese manufacturers, alleging "violation" of its patents.

Ninebot said on a verified social media account that it had purchased "100%" of the New Hampshire-based firm, without stating how much the deal was worth.

"We believe this acquisition is very meaningful for a new generation of Chinese innovation to spread out to the world, and for China to move from manufacturing to invention," it said on China's Twitter-like Sina Weibo.

Segway has a chequered history -- on Christmas day 2009 it was sold to a group led by British millionaire Jimi Heselden, who died months later after driving his Segway off a cliff.

It was later acquired by a group called "Summit Strategic Investments", Segway says on its website.

The Segway was introduced in 2002 amid great fanfare as way to revolutionise urban transport. They use gyroscopes, computers and electric motors to cruise at up to 19 kilometres per hour.

Such machines failed to become a mainstream method of transport but have achieved niche success in China where riders can be spotted in upscale neighbourhoods -- as well as police using them to patrol on Tiananmen Square.

The US International Trade Commission in Washington shows on its website that Segway in November filed a complaint listing six manufacturers it accused of infringing its patents, among them Ninebot.

Ninebot also announced Wednesday that it had received an $80 million investment from Chinese smartphone manufacturer Xiaomi.