Abstract: An example crown assembly includes a button tube, a crown, a spring piece, a switch, and a fastening frame. The crown includes a crown cap and a crown stem that are connected. The spring piece includes a first plate, an elastic arm, and a second plate. Two ends of the elastic arm are connected to the first plate and the second plate. When pressure is exerted on the crown cap, the crown stem is capable of moving along the axis and pushing the first plate away from the end that is of the elastic arm and that is connected to the second plate, to enable the first plate to press the switch. The elastic arm is capable of generating elastic deformation, and when the pressure on the crown cap is released, the first plate is capable of pushing the crown stem away from the switch under elasticity of the elastic arm.

Abstract: A smartwatch, including: a watch frame, a watch core is disposed in the watch frame; and a button, including a button cap, a first button lever and a second button lever, where the button cap is connected to the first button lever, the first button lever is disposed in a button hole provided on the watch frame, and the second button lever is disposed in a button hole opposite to the first button hole provided on the watch core. When the button is in a working state, the first button lever and the second button lever are engaged with each other, and the second button lever can transfer pressure or torque from the button cap. When the button is in a detached state, the first button lever and the second button lever are separated from each other, and the watch core can be taken out of the watch frame.