Sony patents liquid airbag

Sony has filed for a U.S. patent on a liquid airbag for electronics - in particular, for hard disks. The idea is that the electronics will be wrapped in a fluid-filled bag so if the outer case suffers a shock, the liquid acts as a cushion.

The technology is intended for use in mobile devices such as cameras and media players, and could also find its way into business-orientated technology such as smartphones and laptops.

Sony's engineers said that while the use of liquids to absorb shock has been suggested before, previous versions depended on floating the electronics between two immiscible fluids, or using a gel-like viscous substance. They argued that those systems would be difficult to configure and may not provide enough absorption to deal with heavy shocks.

The new scheme proposes that the fluid-filled inner skin will also contain "biasing units" to keep the electronics central, and a system of irises that adjust their resistance to liquid flow according to the force of impact.

The irises are created by protrusions - the patent calls them convex portions and apertures -- aligned opposite each other on the inside walls of the fluid bag. As the walls converge under pressure, the protrusions come closer together and provide increased resistance to the flow of fluid, thereby absorbing more shock.

The liquid used could be water or silicon oil, the Sony boffins said. They added that the electronics would of course be in a liquid-tight case.