Feb. 2010	Obtains a patent for "Double Shock Absorbing Casters " under PAT No.4458960
Sep. 2010	Obtains a patent for "Shock Absorbing Casters V -Torsion spring type-" under PAT No.4579285
Dec. 2010	Obtains a patent for "Shock Absorbing Casters I-B -Advanced coil spring type-" under PAT No.4651658
Sep. 2015	Obtains a patent for "Safety lock castor" under PAT No.5800651
Dec. 2016	Obtains a patent for "The device that can adjust seat inclination angle and the wheelchair to which this device is mountedr" under PAT No.6052693