
After repeatedly witnessing umbrellas flipping inside out and breaking due to strong winds and gusts in the city, we set out to develop a "durable folding umbrella that resists damage even when inverted by wind and can be used for a long time." This led to the development of the frame structure for TOUGHNESS.
To strengthen the joint sections, which are a weak point of folding umbrellas, we arrived at the design concept of "flexibly deflecting stress." Instead of confronting strong winds with rigid strength, we intentionally allow the umbrella to bend flexibly to parry the force of the wind. By adopting highly elastic polycarbonate material for the stretchers, we established an ideal structure that absorbs the impact of wind and prevents damage.
The completed frame structure demonstrated wind resistance in wind tunnel tests conducted by an external organization, proving it would not break even under 30m/s winds from angles of 0, 135, and 180 degrees. Furthermore, it passed a rigorous "100-time inversion test."
Despite its large size with 60cm ribs and 8 main spokes, we combined a thick central shaft and reinforced parts that firmly withstand wind pressure, creating a robust frame that can be used stably even in gusty conditions. This umbrella provides peace of mind for use on windy days and in adverse weather.