Gas cylinder

Abstract

A gas cylinder includes a spindle vertically reciprocating along a center shaft, a cylinder installed in the spindle and filled with gas, a piston member sectioning an inside of the cylinder into an upper portion and a lower portion, and a valve member sealing an upper end of the cylinder and controlling flow of the gas filling the inside of the cylinder. The valve member includes a pipe holder sealing an upper end of the cylinder, an open pin inserted in the pipe holder by penetrating the pipe holder, and a sealing member provided at an end portion of the open pin to contact the pipe holder. When the open pin is inclined by a predetermined angle with respect to the center shaft, a gap is formed between the sealing member and the pipe holder so that the flow of the gas is controlled.

1 . A gas cylinder for a chair vertically reciprocating along a center shaft, the gas cylinder formed to enable vertical reciprocation of the chair when an open pin controlling a flow of gas filling an inside of the gas cylinder is pressed in any of an axial direction along the center shaft and a direction substantially perpendicular to the center shaft. 
     
     
         2 . The gas cylinder of  claim 1 , comprising:
 a cylinder filled with gas; and   a pipe holder sealing an end portion of the cylinder,   wherein the vertical reciprocation of the chair is controlled according to whether the open pin and the pipe holder are closely contacted or not.   
     
     
         3 . The gas cylinder of  claim 2 , wherein, when the open pin is pressed in the axial direction of the center shaft, the open pin and the pipe holder are separated from each other. 
     
     
         4 . The gas cylinder of  claim 2 , wherein, when the open pin is pressed in the direction substantially perpendicular to the center shaft, the open pin is inclined with respect to the pipe holder at a contact point where the open pin contacts the pipe holder. 
     
     
         5 . A gas cylinder comprising:
 a spindle vertically reciprocating along a center shaft;   a cylinder installed in the spindle and filled with gas;   a piston member sectioning an inside of the cylinder into an upper portion and a lower portion; and   a valve member sealing an upper end of the cylinder and controlling flow of the gas filling the inside of the cylinder,   wherein the valve member comprises:   a pipe holder sealing an upper end of the cylinder;   an open pin inserted in the pipe holder by penetrating the pipe holder; and   a sealing member provided at an end portion of the open pin to contact the pipe holder, and   wherein, when the open pin is inclined by a predetermined angle with respect to the center shaft, a gap is formed between the sealing member and the pipe holder, thus controlling the flow of the gas.   
     
     
         6 . The gas cylinder of  claim 5 , wherein, when the open pin is pressed by an external force, the open pin is inclined by a predetermined angle with respect to the center shaft at a contact point between the sealing member and the pipe holder, thus forming the gap between the sealing member and the pipe holder. 
     
     
         7 . The gas cylinder of  claim 5 , wherein, when the pipe holder and the sealing member closely contact each other, the flow of the gas is stopped and, when the pipe holder and the sealing member are separated from each other, the gap is open to make the gas flow through the gap. 
     
     
         8 . The gas cylinder of  claim 5 , wherein the pipe holder further comprises a washer arranged in the pipe holder and the washer and the sealing member contact each other. 
     
     
         9 . The gas cylinder of  claim 5 , wherein the valve member further comprises a packing member encompassing the sealing member. 
     
     
         10 . The gas cylinder of  claim 5 , wherein a hollow portion in which the open pin is inserted by penetrating the hollow portion is formed in the pipe holder and the inner diameter of the hollow portion is larger than the outer diameter of the open pin. 
     
     
         11 . The gas cylinder of  claim 10 , wherein an O-ring is interposed between the pipe holder and the open pin. 
     
     
         12 . The gas cylinder of  claim 10 , wherein the diameter of the sealing member is large than that of the hollow portion, thus the sealing member covering the hollow portion. 
     
     
         13 . The gas cylinder of  claim 5 , wherein, when the open pin is pressed in the axial direction along the center shaft, the sealing member and the pipe holder are separated from each other, thus controlling the flow of the gas. 
     
     
         14 . The gas cylinder of  claim 5 , wherein the pipe holder comprises an inner holder and a washer which are arranged in the pipe holder, and the inner holder and the washer are formed of materials different from each other. 
     
     
         15 . The gas cylinder of  claim 14 , wherein the inner holder is formed of a synthetic resin based material. 
     
     
         16 . The gas cylinder of  claim 14 , wherein the washer is formed of a metal based material and the washer and the sealing member contact each other. 
     
     
         17 . A gas cylinder for a chair, the gas cylinder comprising:
 a cylinder;   a pipe holder arranged in an upper portion of the cylinder;   an open pin inserted in the pipe holder by penetrating the pipe holder; and   a sealing member formed at an end portion of the open pin,   wherein the open pin and the sealing member are capable of pivoting with respect to the pipe holder.   
     
     
         18 . The gas cylinder of  claim 17 , wherein, when the open pin and the sealing member pivot with respect to the pipe holder, gas flows between the sealing member and the pipe holder. 
     
     
         19 . The gas cylinder of  claim 17 , wherein the open pin pivots with respect to a contact point between the sealing member and the pipe holder. 
     
     
         20 . The gas cylinder of  claim 17 , wherein a hollow portion in which the open pin is inserted by penetrating the hollow portion is formed in the pipe holder and the sealing member covers an end portion of the hollow portion.