Locking device

A combination of a locking device and a fan with fan blades, the locking device comprising an arc-shaped strip, the arc-shaped strip comprising a first end, a second end, and an outer wall, wherein:

• the first end comprises an upper convex block and a left side end;
• the second end comprises a lower convex block and a right side end;
• the upper convex block protrudes from the left side end and the lower convex block protrudes from the right side end;
• the upper convex block and the lower convex block are misaligned to form a middle aperture;
• a left aperture is formed between the left side end and the lower convex block, and a right aperture is formed between the right side end and the upper convex block;
• an upper convex ear protrudes from the outer side of the upper convex block and a lower convex ear protrudes from the outer side of the lower convex block;
• the upper convex ear corresponds to the lower convex ear with respect to their positions;
• the upper convex block and the lower convex block are respectively arranged with an upper guiding inclined plane and a lower guiding inclined plane;
• the upper convex ear comprises a through hole, and the lower convex ear comprises a mounting hole;
• the through hole of the upper convex ear and the mounting hole of the lower convex ear are axially connected using a bolt-nut mechanism or screws to lock the upper convex ear and the lower convex ear;
• the upper convex block and the lower convex block move axially to narrow the middle aperture;
• the upper guiding inclined plane and the lower guiding inclined plane contact with each other to make the upper convex block and the lower convex block to move circumferentially to narrow both the left aperture and the right aperture and enable the the first end and the second end to be connected to form a hoop having an axial mounting hole in the middle to tightly hold an object inside the axial mounting hole:
• the fan blades are connected to the outer wall via mounting foots;
• and
• a balancing structure is arranged either on the mounting foots or the arc-shaped strip to eliminate dynamic imbalance caused by the bolt-nut mechanism or the screws.