Briggs & Stratton puts Lynch motor into mass production

The novel high-efficiency DC pancake motor developed by the British inventor Cedric Lynch is going into volume production in China following an agreement between Lynch`s Lemco company and the US petrol engine giant, Briggs & Stratton.

The move marks Briggs & Stratton`s first venture into electric motors and could create a vast market for the Lynch motors in applications such as lawnmowers, forklift trucks, wheelchairs and golfcarts. The company, with annual sales of $1,500m, is already the world`s largest producer of air-cooled petrol engines up to 25hp.

Cedric Lynch has been working on his designs for almost two decades but until now production of his motors has been limited to a small number of machines handbuilt at Lemco`s plant in Honiton, Devon. The ironless Lynch motor is the first to combine the advantages of a disc armature with those of a conventional traction motor, resulting in higher efficiencies and power-to-weight ratios than most competing DC machines. It is about a third of the size of motors typically used in forklift trucks and has an efficiency of around 90% - about 10% higher than a conventional traction motor. These factors extend the battery life.

Initially, Briggs & Stratton is building the Lynch motor in two versions in a new factory it has set up in China. One version, rated at 1.5kW, is aimed at applications such as golfkarts; the other, rated at 4.5kW, is intended for forklift trucks and similar vehicles. Later this year, a new version, designed for power steering applications, will go into production.

The potential market is huge. In the US alone, 120,000 golfcarts are sold every year by three main manufacturers and Briggs & Stratton is working closely with one of them to incorporate Lynch machines into their carts. Lemco will sell the motors in the UK.

Lynch`s partner Trevor Lees thinks that the availability of larger number of lower cost machines could open up new markets. "Before, if someone came to us with an order for 1,000 motors, we couldn`t do it," he says. "Now it`s no problem."

Following the licensing agreement with Briggs & Stratton, other large potential users have been taking a closer interest in the Lynch technology. "It gives us credibility," says Lees. The Briggs & Stratton agreement is limited to specific applications.

Lemco, which at one time attracted financial support from the electricity generator Powergen, is now owned by a Swiss electric vehicle specialist, Asmo Engineering, which has sold more than 500 Lynch-powered electric go-karts.