A spring lock for a skate wheel includes a housing including opposite first and second holes, and a third hole; a pin through the first and second holes and including first and second grooves; a button on the third hole; a back plate on a back of the housing; a first biasing member secured to the back plate; a stop member secured to the first groove; a sliding member having one end urging against the first biasing member and the other end contacting the button to slidably dispose on the second groove, the sliding member including small and large holes; and a second biasing member on the pin and having one end urging against an inner surface of the housing and the other end urging against the stop member. In a locked state, the pin extends into an elongated hole of between two spokes of the wheel.

The disclosure relates to a wheel extending and retracting device for dual-purpose shoes which includes: a housing and a housing cover. A front end and a rear end of the housing are rotatably connected to a front wheel carrier and a rear wheel carrier respectively, a control assembly is mounted on the housing, and a vertical limit hole is provided in the housing. The control assembly drives a locking movable shaft, and the locking movable shaft is driven by the control assembly so as to vertically move along the vertical limit hole. A retracting snap-in recess and an extending snap-in recess that are configured to snap in the locking movable shaft are provided in the rear wheel carrier. Two sides of the housing are provided with attachment steps that protrude outwards, and an outer side of the attachment step is provided with a linkage frame in an abutted manner.

The disclosure relates to a wheel extending and retracting device for dual-purpose shoes which includes: a housing and a housing cover. A front end and a rear end of the housing are rotatably connected to a front wheel carrier and a rear wheel carrier respectively, a control assembly is mounted on the housing, and a vertical limit hole is provided in the housing. The control assembly drives a locking movable shaft, and the locking movable shaft is driven by the control assembly so as to vertically move along the vertical limit hole. A retracting snap-in recess and an extending snap-in recess that are configured to snap in the locking movable shaft are provided in the rear wheel carrier. Two sides of the housing are provided with attachment steps that protrude outwards, and an outer side of the attachment step is provided with a linkage frame in an abutted manner.