A technology originally designed for separating oil and gas is at the heart of Hoover’s latest vacuum cleaner. Wellsep, which was developed by BHR Group, has been miniaturised to allow Hoover to build a bagless vacuum cleaner and strike back at rival Dyson’s market-leading dual-cyclone design.
Adapting Wellsep’s ‘amplified spin-cleaning’ technology, BHR Group’s Cranfield-based engineers developed an arrangement of vortex-inducing devices which recirculate air until it is clean. Called the Triple Vortex system, the separator consists of a multi-stage vortex with a built-in feedback loop.
A first-stage vortex is induced in the dust container to spin out more than 90% of the dirt. The semi-cleaned air is then drawn into a second-stage involute separator which uses a high-velocity vortex to concentrate fine dirt into about 20% of the air flow.
This portion of the air flow is then cleaned using a third-stage miniature cyclone small cyclones generate higher g-forces and are better at removing the finest particles.
Transport air from the third stage is re-injected into the second-stage vortex for a final scrub before exiting clean. It is this final stage and recycle which differentiates the BHR Group design from the Dyson dual cyclone system.
Wellsep, the technology on which the Triple Vortex is based, is a compact in-line two-phase separator which operates at very low pressure drops. It is used for gas-liquid, gas-solid or liquid-solid separation.
Wellsep technology was first suggested as a possible application for vacuum cleaners in 1997 when BHR Group was looking to commercially exploit more of its technologies.
The first prototype used Wellsep’s spiral spinner to induce a cyclone. But with a dust container the size of a dustbin it was deemed too large.
A smaller prototype followed a month later. This time it was judged good enough to show to firms which could bring it to the market. Hoover was invited to view the machine. It was impressed, but development continued, with the Wellsep spinner being replaced by an involute separator. The final touch was the feedback of air into the eye of the cyclone, which polished the exiting air stream.
The Vortex vacuum cleaner is powered by a 1350W motor and has a dust storage capacity of 2 litres. An S-class filter will be available to boost filtration to 99.99% of dust down to 0.3 microns.
The cleaners are being manufactured by Hoover in Cambuslang, near Glasgow.