shadoof; well sweep; counterweighted water bucket
A traditional device for drawing water from a well, consisting of a bucket suspended from a long pivoting rod with a counterweight. The term is specific to Japanese well technology and may be unfamiliar to modern speakers.
In old wells, a shadoof was often used.
I saw the mechanism of a well sweep at the museum.
Compound of 撥ね (hane, 'springing' or 'flipping') and 釣瓶 (tsurube, 'well bucket'). The name describes the pivoting motion of the weighted rod that lifts the bucket.