Damping and parking two-in-one device for bicycle trailer

The utility model discloses a bicycle trailer damping and parking two-in-one device which comprises a frame, a hollow triangular swing arm, an adjustable damping spring assembly, a parking pin, a parking device shell, a parking device spring, a rotating shaft pin, a wheel shaft sleeve, a hollow bolt, a sealing cover, a quick-release axle, a parking disc, wheels, a first support, a second support and a brake cable. The first support and the second support are both located on the two sides of one end of the frame, the hollow triangular swing arm is arranged at the upper end of the first support, the hollow triangular swing arm is connected with the wheel and the adjustable damping spring assembly, and the parking device shell and the parking pin are both embedded in the middle of the hollow triangular swing arm. The bicycle trailer has the advantages of being compact in structure and easy to install, extra parking and damping functions can be provided for the bicycle trailer, and the packing size cannot be incr