[0011] U.S. Pat. No. 5,749,170 to F

[0011] U.S. Pat. No. 5,749,170 to Furuta (1998) reveals an automatic water supply device. The device comprises a pot-shaped case, a reverse bowl shape, and a flowerpot with drain holes. The reverse bowl is placed at the bottom. The flow pot is placed above the reverse bowl. The water is poured into the case. The water flows into the reverse bowl, which has an air gap on the dome. Air pressure is applied to the reverse bowl and to push the water upward to the space between the case and flowerpot. The water wets the soil from bottom up. The watering sequence is controlled by two means. A timer can be set to drive an air pump, which pump air to the reverse bowl. A soil moisture sensor can also send a signal to the controller, which operates the air pump. The Furuta device shares the same disadvantages of self-watering planters.