This is a wind chime. It will not ring when there is no wind, but it will make a sound when there is wind.
It is a bell commonly used in Japan.
The function of wind chimes is to give people a cool feeling.
The sound of wind chimes is very similar to the cry of a kind of insect in autumn. Listening to the sound of wind chimes can make you feel better in summer, and it can play the role of looking for plum blossoms and quenching thirst.