Locking device and assembly

An assembly comprising:

• a locking device comprising:
• a sleeve having an assembly through hole and a restricting through hole, wherein the assembly through hole extends through the sleeve along an axial direction of the sleeve, the restricting through hole is formed on a side face of the sleeve and is in fluid communication with the assembly through hole, and an end face of the sleeve has an accommodating portion;
• a locking member movably assembled in the restricting through hole;
• a restricting member comprising a first guide portion and a restricting protrusion connected to each other, wherein the first guide portion is rotatably assembled in the assembly through hole, at least a portion of the first guide portion is aligned to the restricting through hole, the restricting protrusion abuts an end of the sleeve, and the restricting protrusion is configured to rotate on the end face of the sleeve to the accommodating portion as the restricting member rotates;
• and
• a resilient member installed in a chamber formed by the restricting member and the sleeve, wherein the resilient member is configured to apply a force to the sleeve to move the restricting protrusion into the accommodating portion, and the first guide portion is configured to push the locking member to move in the restricting through hole in a direction away from the axis of the sleeve;
• and
• at least two locking target units stacked together, each locking target unit having a hole;
• wherein
• the locking member is configured to pass through the hole of the at least two locking target units, and the locking member is configured to abut a wall of one of the holes of the locking target units.