Gas cylinder

A gas cylinder comprising:

• an integral type valve having a gas opening/closing pin at a through hole in its center, for intermittently passing a gas, and additionally having a valve dividing body seated on a groove approximately in a lower part of the through hole, for supporting positions of inner parts;
• a spindle, to an upper inside of which the valve is inserted;
• a piston inserted to an inside of the spindle and having a step threshold formed on an outer periphery at a predetermined distance from an upper end, and to which an O-ring for maintaining sealing is fit, and having another step threshold to which an O-ring is fit on an inner lateral surface of the piston, ranging from a lower side of the step threshold to a lower end;
• a washer additionally formed on an upper end of the piston, for fixing position of the O-ring;
• a piston rod whose one end is inserted and fixed to the piston;
• and
• a base tube of a cylindrical shape, in a lower side of which the other end of the piston rod is fixed by means of a fixing clip and whose inner peripheral surface guides up and down movement of the spindle.

A gas cylinder comprising:

• an integral type valve having a gas opening/closing pin at a through hole in its center, for intermittently passing a gas;
• a spindle, to an upper inside of which the valve is inserted;
• a piston inserted to an inside of an open cylinder of the spindle;
• a piston rod whose one end is inserted and fixed to the piston;
• a fixing clip made of elastic material, for fixing the other end of the piston rod, and is bent in an U-shape so that one side and the other side whose ends face each other are formed, wherein the one side has a cut whose width, from the end part, is smaller than a diameter of the piston rod and larger than a diameter of a groove of the piston rod, for being fit in the groove of the piston rod, and the other side has, apart a predetermined distance from an end part, a cut whose width is larger than a diameter of the piston rod, so that a lower end of the piston rod goes by a predetermined distance between the one side and the other side, and then passes through to a lower part, and a pressing part extended from the cut formed on the other side, for pressing the lower end of the piston rod, is provided;
• and
• a base tube of a cylindrical shape, to which the piston rod is inserted.

A gas cylinder comprising:

• an integral type valve having a gas opening/closing pin at a through hole in its center, for intermittently passing a gas;
• a spindle to an upper inside of which the valve is inserted;
• a piston inserted to an inside of an open cylinder of the spindle;
• a piston rod whose one end is inserted and fixed to the piston;
• and
• a base tube of a cylindrical shape, in which the other end of the piston rod is fixed, and to which the piston rod is inserted, and whose lower end is bent inward, forming a lower bending part for removing unevenness or projecting part due to thermal transformation of the base tube.