Reliable-working bidirectional safety gear

The utility model discloses a reliable-working bidirectional safety gear. A guide hole is formed in an end plate of a mounting frame, a brake roller linkage rod is arranged in the guide hole in a penetrating mode, a lifting plate is fixed on the brake roller linkage rod, a sliding groove with the extending direction perpendicular to two side plates is formed in the lifting plate in each of the two sides of the brake roller linkage rod, a drive wedge is fixed on the inside of each of the side plates, the opposite surfaces of the two drive wedges are V-shaped surfaces, a limit plate is fixed on the inside of each of the side plates, V-shaped sliding grooves are opened in the limit plates, two square friction blocks are arranged between the two drive wedges and are in sliding contact fit with the V-shaped surfaces of the two drive wedges respectively, a gap is formed between the two friction blocks, and the two ends of a mounting shaft in the two friction blocks are inserted in the corresponding sliding grooves