Supporting framework for a swivel chair or swivel table

A supporting framework for a piece of swivel furniture, comprising:

• a gas spring;
• a cylinder put on the gas spring and comprising two opposite holes, a top annular flange, and a plurality of equally circumferentially spaced longitudinal apertures, each aperture being open to the flange;
• a plurality of posts;
• a plurality of lock bars;
• a plurality of springs loaded said posts disposed in a first group of said apertures;
• a plurality of springs loaded said lock bars disposed a second group of said apertures, wherein the number of the apertures in the second group being equal to that in the first group, and the lock bar being shorter than the post;
• a ring rested upon the cylinder with the gas spring projected therethrough and fastened thereby, the ring comprising a plurality of equally circumferentially spaced openings, the opening having a diameter less than a diameter of the post such that the post is urged upward against the opening but slightly larger than a diameter of the lock bar such that the lock bar is adapted to enter into the opening;
• a sleeve put on the cylinder, the sleeve comprising two opposite lock holes;
• and
• a hollow cap with the gas spring projected therethrough, the cap comprising two opposite channels of inverted-L shape on its peripheral wall, and two lock pins adapted to insert through the channels and the lock holes into the holes for fastening the cap, the sleeve, and the cylinder together;
• whereby:
• rotating the cap a small predetermined angle, and lifting same will move the lock pins from upper second positions to lower first positions of the channels to enable the gas spring to rotate freely for adjusting an orientation of the piece of swivel furniture;
• and
• pressing the cap and rotating same will move the lock pins from the lower first positions to the upper second positions of the channels, and rotating the gas spring a small predetermined angle will align the openings with the lock bars for raising the lock bars to enter into the openings for locking the gas spring after the piece of swivel furniture has been positioned in the orientation adjustment.