Abstract: A gas filtering device for a light gas tank includes a tank, a control valve, a filter, a position block and a position bolt. The control valve is combined with a center hole of the tank body and has a passageway communicating with a hollow interior of the tank, with the filter positioned under the lower end of the passageway. Thus fuel gas is filtered become pure with water and miscellaneous matters removed by the filter when it flows out, so fuel gas may burn completely, with heat energy elevated in burning.

Abstract: A light gas tank with a safe inlet device includes a ring fixed on an upper surface of a light gas tank. The ring has a center fuel inlet hole, and an inverted L-shaped gas inlet on one side of the wall and an inverted L-shaped passageway on the other side of the wall. An L-shaped air tube is located in a hollow interior of the tank, having its upper end welded with a vertical portion of the gas inlet and air holes in a lower portion. An air pumping device can pump air into an inlet nozzle, the gas inlet of the ring and the L-shaped air tube, and then out of the air holes into the fuel stored in the tank to fuse with the fuel to become fuel gas for use through a control valve fixed on the tank. The pumping device is operated only when fuel gas is to be used, so no large gas pressure is produced in the tank, diminishing potent danger of explosion.