A seal for barrel shaped cylinder

Abstract

A helical coiled seal for sealing a barrel-shaped cylinder piston-cylinder assembly, comprising: a piston-sealing C-shaped ring; a connecting C-shaped ring comprising an inward wing protruded inwardly from a section near a first end on an inner perimeter of the connecting C-shaped ring, and an outward wing protruded outwardly from a section near a second end on an outer perimeter of the connecting C-shaped ring; and a cylinder-sealing C-ring; wherein the piston-sealing C-ring is connected end-to-end to the first end of the connecting C-ring and cylinder-sealing C-ring is connected end-to-end to the second end of the connecting C-ring forming a three-ring helical structure having a contraction-dilation response time sufficiently short required for the up-down stroke speed of the cylinder piston-cylinder assembly.

What is claimed is: 
     
         1 . A helical coiled seal for sealing a piston-cylinder assembly, comprising:
 a piston-sealing C-shaped ring having a first gap;   a connecting C-shaped ring comprising:
 an inward wing protruded inwardly from a section on an inner perimeter of the connecting C-shaped ring near a first end of the connecting C-shaped ring; and 
 an outward wing protruded outwardly from a section on an outer perimeter of the connecting C-shaped ring near a second end of the connecting C-shaped ring; and 
   a cylinder-sealing C-shaped ring having a second gap;   wherein the piston-sealing C-shaped ring is connected end-to-end to the first end of the connecting C-shaped ring and cylinder-sealing C-shaped ring is connected end-to-end to the second end of the connecting C-shaped ring forming a helical coil;   wherein the inward wing width allows the inward wing inner perimeter to align with the piston-sealing C-shaped ring inner perimeter;   wherein the outward wing width allows the outward wing outer perimeter to align with the cylinder-sealing C-shaped ring outer perimeter.   wherein the inward wing length is equal or longer than the first gap such that the piston-sealing C-shaped ring with the inward wing form an at least 360 degree piston surface sealing contact; and   wherein the outward wing length is equal or longer than the second gap such that the piston-sealing C-shaped ring with the outward wing form an at least 360 degree cylinder interior wall sealing contact.   
     
     
         2 . The helical coiled seal of  claim 1 , wherein the helical coiled seal is made of copper, phosphor bronze, or other alloys with high heat transfer characteristics. 
     
     
         3 . A piston-cylinder assembly, comprising:
 a cylinder having an interior wall; and   a piston that is disposed inside the cylinder;   wherein the piston being tightly encircled radially by one or more rings of the helical coiled seal of  claim 1 ; and   wherein the cylinder being intimately contacted by one or more rings of the helical coiled seal of  claim 1  providing sealing function to the piston-cylinder assembly.