| 摘要 |
<p>The present invention provides a boomerang device characterised in that it comprises a flat central ring member (10) having inner and outer substantially circular boundaries (12, 13) and defining a central aperture (14), at least two wing members (11) projecting outwardly from the outer boundary of the ring (10), each wing member (11) being of asymmetrical aerofoil section and being arranged to act in the same direction as all of the other wings (11), such that when the device is thrown with a rotary motion the wings (11) produce lift and also turn.</p> |
