灯油ポンプのしくみ　・なぜ灯油は一方方向に移動するのか？・移動が始まると、勝手に移動が続くのはなぜか？ポンプの上のねじは、何のためについているのか？管の先が斜めになっているのはなぜか？

Kerosene pumps are a familiar tool, and they're full of ingenious features. 0:00 Why does it move in one direction? (Valve) 2:10 Why does kerosene move on its own halfway through? (Siphon principle) 5:18 How the pump's cap (screw) works 10:13 Why is the end of the tube slanted? The original kerosene pump was invented by inventor Dr. Nakamatsu. At the time, Nakamatsu, a junior high school student, saw his mother struggling to dispense soy sauce from a 1.8L bottle. He thought, "I wish there was an easier way to dispense it," and invented the "Shoyu Churu Churu," a device similar to a kerosene pump. While some have suggested the slanted end of the tube is "to allow kerosene to be absorbed all the way to the edge of the container," we chose the idea that it allows any kerosene remaining in the tube to be smoothly returned to its original position. When observing how the liquid falls, we see that air rises from one side of the tube (the shorter side) and water falls from the other side (the longer side), so they are neatly replaced. This is where we sensed the designer's intention.