Coventry-based Bladon Jets (UK), a global leader in the development and manufacture of small, multi-fuel, micro-jet gas turbine engines, is underpinning its patented technology with two recently installed Sodick EDM machines. Currently participating in development projects with many leading automotive OEMs, Bladon Jets is aiming to power the cars of the future.

The proprietary micro-jet engines developed by the company are lighter, less polluting and cheaper than the 100 year old reciprocating combustion engines used in almost all cars today. The immediate and near future target market is electric vehicles.

The problem with electric cars is their range. Using current technologies users can only drive 80-160km before having to stop and charge the batteries. To solve this, an alternative power source is required. Modern hybrids use traditional piston driven car engines but these are heavy, complex and can only operate using a single type of fuel – petrol or diesel.

“By comparison, gas turbine engines are very light – 3kg compared to over 100kg for a piston engine – and have only one moving part, not 2,500, making them simpler to produce and maintain,” says Bladon’s company director Phillip Lelliott. “They are efficient, green, offer multi-fuel capability and exhibit very high power to weight ratios. Additionally they require no water cooling system, oil or catalytic converter.”

Perhaps the biggest challenge is producing the ‘miniature’ series of integrally bladed disks (or blisks) that compress the air as it flows axially through the turbo-shaft engine. The engine is coupled to a high speed generator that charges the batteries, making it an ideal onboard power source (or range extender) for an HEV.

“The blisks are not only small – they exhibit complex profiles and demand watchmaker-type precision, if not more,” says Mr Lelliott. “We realised early on that conventional machining techniques such as milling were simply not possible due to access restrictions so we looked at EDM and hit upon real success – so much so that we now have a number of patents hinging around the use of EDM to produce these blades.”

Bladon Jets has initially installed a reconditioned Sodick AQ325L wire machine and a brand new Sodick AG35L die sink EDM. Each is configured differently to produce different parts. The latter, for example, features a 32 station toolchanger that allows the company to run around the clock producing development components. According to Sodick, the AG35L is the market’s fastest, high precision die sink EDM. It also features linear motor technology in the X, Y and Z axes, as well as Sodick Motion Control (SMC) for optimal spark gaps. The AQ325L is a 4-axis wire machine (all with linear motors) featuring automatic wire threading capability.

Typically, each micro-jet engine has three or four different blade sizes – each with a different shape/profile, varying section, edge radii and taper from root to tip. At the front (cold) end of the engine, aircraft specification aluminium is the normal blade material, while at the hot end Nimonic alloy is more typical.

Bladon Jets is in discussions with a number of car manufacturers. Among the models to feature the technology is the Jaguar C-X75 concept car, a two seater electric hybrid that uses twin micro-jet engines to travel 900km on a 60 litre tank of fuel. It can sprint from 0 to 62mph in just 3.5 seconds and achieve a top speed of 205mph. No wonder it is already being described as the ‘E-Type for the 21st century’. At present it is a concept vehicle but it demonstrates Jaguar’s ambitious vision for the future of electric car travel.

A Jaguar spokesperson comments: “The C-X75 demonstrates it is possible to retain Jaguar’s core values of performance, design and luxury using technology that will make environmentally responsible performance and electrical vehicles a practical proposition.”

Sodi-Tech EDM
www.sodi-techedm.co.uk

Bladon Jets (UK)
www.bladonjets.com