Sturdy, Compact, Collapsible Camping Chair

Abstract

A collapsible chair includes upper tubes, leg tubes, a central tube connector and a seat back. The tube connector has two first tubes bent around a central cylinder from below and two second tubes bent around the central cylinder from above. The first and second tubes are welded to the central cylinder. Upper holes are formed by the ends of the first tubes, and lower holes are formed by the ends of the second tubes. Lower ends of the upper tubes are inserted into the upper holes, and upper ends of the leg tubes are inserted into the lower holes. Upper ends of the upper tubes fit into tube receptacles in the seat back. No part of the upper tubes other than the upper and lower ends contacts any part of the chair. The two back upper tubes are bent and are longer than the two straight front upper tubes.

What is claimed is: 
     
         1 . A collapsible chair comprising:
 upper tubes with lower ends and seat ends, wherein the lower ends have circular cross setions;   leg tubes with upper ends;   a seat back with tube receptacles;   a central cylinder;   two first short bent tubes that bend around the central cylinder from below and that are welded to the central cylinder, wherein four upper holes with circular circumferences are formed at ends of the first tubes; and   two second short bent tubes that bend around the central cylinder from above and that are welded to the central cylinder, wherein four lower holes with circular circumferences are formed at ends of the second tubes, wherein the lower ends of the upper tubes are detachably connected to the first bent tubes by being inserted into the upper holes, wherein the upper ends of the leg tubes are detachably connected to the second bent tubes by being inserted into the lower holes, wherein the seat ends of the upper tubes are detachably connected to the tube receptacles, and wherein no part of the upper tubes other than the lower ends and the seat ends contacts any part of the collapsible chair.   
     
     
         2 . The collapsible chair of  claim 1 , wherein the upper tubes consist of two tubes of a first length and two tubes of a second length, and wherein the first length is longer than the second length. 
     
     
         3 . The collapsible chair of  claim 2 , wherein each of the two tubes of the first length is bent, and wherein neither of the two tubes of the second length is bent. 
     
     
         4 . The collapsible chair of  claim 2 , wherein each of the upper tubes of the first length has a lower section, a middle section and an upper section, wherein the lower end of each upper tube of the first length is disposed on the lower section of the upper tube, wherein each lower section is curved, and wherein each middle section and each upper section is straight. 
     
     
         5 . The collapsible chair of  claim 1 , wherein the central cylinder has a diameter that is larger than the diameter of the upper tubes. 
     
     
         6 . The collapsible chair of  claim 1 , wherein each of the upper tubes is comprised of detachable sections. 
     
     
         7 . The collapsible chair of  claim 1 , wherein the circular cross section of each of the lower ends is dimensioned to fit snugly into the circular circumference of a corresponding upper hole. 
     
     
         8 . The collapsible chair of  claim 1 , wherein the upper tubes consist of four tubes, and wherein the seat ends fit into the tube receptacles at four corners of the seat back. 
     
     
         9 . The collapsible chair of  claim 1 , wherein the seat back is made of fabric. 
     
     
         10 . The collapsible chair of  claim 1 , further comprising:
 an elastic cord that passes through one of the first short bent tubes and into one of the upper tubes.   
     
     
         11 . A collapsible chair comprising:
 a seat back with tube receptacles; and   a frame made of metal tubes, wherein the frame comprises:
 upper tubes with lower ends and seat ends, wherein the lower ends have circular cross sections; 
 a central tube whose diameter is larger than that of the upper tubes; and 
 means for forming upper holes with circular circumferences, wherein the lower ends of the upper tubes are detachably connected to the means by being inserted into the upper holes, wherein the means bends around and is welded to the central cylinder, and wherein the seat ends of the upper tubes are detachably connected to the tube receptacles. 
   
     
     
         12 . The collapsible chair of  claim 11 , further comprising:
 an elastic cord that passes through one of the upper tubes and into the means.   
     
     
         13 . The collapsible chair of  claim 11 , wherein the frame further comprises leg tubes with upper ends, wherein the means is also for forming lower holes with circular circumferences, and wherein the upper ends of the leg tubes are detachably connected to the means by being inserted into the lower holes. 
     
     
         14 . The collapsible chair of  claim 11 , wherein the upper tubes include two tubes of a first length and two tubes of a second length, and wherein the first length is longer than the second length. 
     
     
         15 . The collapsible chair of  claim 14 , wherein each of the two tubes of the first length is bent, and wherein neither of the two tubes of the second length is bent. 
     
     
         16 . The collapsible chair of  claim 14 , wherein each of the upper tubes of the first length has a lower section, a middle section and an upper section, wherein the lower end of each upper tube of the first length is disposed on the lower section of the upper tube, wherein each lower section is bent, and wherein each middle section and each upper section is not bent. 
     
     
         17 . A method comprising:
 forming upper tubes with lower ends and seat ends, wherein the upper tubes are formed in sections, and wherein the lower ends have circular cross setions;   forming leg tubes with upper ends;   bending first tubes around a central cylinder from below and welding the first tubes to the central cylinder, wherein upper holes with circular circumferences are disposed at ends of the first tubes, and wherein the circular cross sections of the lower ends are dimensioned to fit snugly into the circular circumferences of the upper holes;   bending second tubes around the central cylinder from above and welding the second tubes to the central cylinder, wherein lower holes with circular circumferences are disposed at ends of the second tubes, and wherein the upper ends of the leg tubes are dimensioned to fit snugly into the lower holes; and   making a seat back with tube receptacles disposed at locations on the seat back so as to fit over the seat ends of the upper tubes.   
     
     
         18 . The method of  claim 17 , further comprising:
 pulling an elastic cord through one of the first tubes and into one of the upper tubes.   
     
     
         19 . The method of  claim 17 , wherein the central cylinder has a diameter that is larger than that of the upper tubes. 
     
     
         20 . The method of  claim 17 , further comprising:
 placing the upper tubes, the leg tubes, the central cylinder, the first tubes, the second tubes and the seat back in a bag that is less than one foot long.