BIM had registered Patent, ZL 2022 2 3112418.0
BIM was fitted on Requlor and Lightweight Model。
A single nylon cord penetrates and interconnects all of the blades one by one to knit a three close-loop circle/mesh along the radial direction. BIM is simple but very important for safety.
The function of BIM at some circumstances similar to that of seatbelt in car, it will only be activated when the blade broken, the fractured blade will be held by the Mesh to protect the people underneath.
Before BIM, several measures had been used as protection or safety advice to prevent fractured blade from falling down, such as safety retained links etc.
The patent was inspired by a real accident. A fractured blade was fixed at the root place by safety retained links but the fan was still rotating, the hanging blade just like a rotating knife, described by a witness, all of the people under the whole fan area might be hurt by the blade tail since its height was only 1.8 meters high. The site manager complained later that in such case they would like the blade fall rather than its hanging in air, as it could lead to an even more serious hurt accident than just one fractured blade fall.
