Compressor and/or expander device with rolling piston seal

Abstract

An apparatus can include a piston movably disposed within a pressure vessel and defines a first interior region and a second interior region. The piston has a first position in which the first interior contains a gas having a first pressure and has a volume greater than the second interior region, and a second position in which the second interior region contains a gas having a second pressure and has a volume greater than the first interior region. A seal member is attached to the piston and to the pressure vessel. The seal member has a first configuration in which at least a portion of the seal member is disposed at a first position when the piston is in its first position, and a second configuration in which the portion of the seal member is disposed at a second position when the piston is in its second position.

1 .- 30 . (canceled) 
     
     
         31 . A flexible seal member adapted to seal a clearance gap between a cylinder and a reciprocating piston disposed therein, the seal member comprising:
 first and second end portions adapted to attach to the cylinder; and   a rib circumferentially disposed at an intermediate portion of the seal member, the seal member adapted to attach to the reciprocating piston within the cylinder by the rib;   wherein the intermediate portion of the seal member is adapted to move relative to the end portions of the seal member during reciprocation of the piston.   
     
     
         32 . The seal member of  claim 31 , wherein the first end portion comprises a rod forming a bead and wherein the first end portion is adapted to attach to the cylinder by clamping the bead thereto. 
     
     
         33 . The seal member of  claim 32 , wherein the rod is disposed within a folded-over edge of the first end portion of the seal member. 
     
     
         34 . The seal member of  claim 32 , wherein the second end portion comprises a second rod forming a second bead and wherein the second end portion is adapted to attach to the cylinder by clamping the second bead thereto. 
     
     
         35 . The seal member of  claim 31 , wherein the seal member comprises a flexible sheet adapted to roll upon itself in a direction parallel to a direction of movement of the piston. 
     
     
         36 . The seal member of  claim 31 , wherein the seal member comprises a cylindrical sheet disposed around an outer diameter of the piston. 
     
     
         37 . The seal member of  claim 31 , wherein the seal member comprises a plurality of reinforcement members embedded in a flexible rubber material. 
     
     
         38 . The seal member of  claim 31 , wherein the seal member is adapted to define a seal interior region for receiving a fluid. 
     
     
         39 . The seal member of  claim 38 , wherein the seal member is adapted to receive pressurized fluid into the seal interior region. 
     
     
         40 . The seal member of  claim 31 , wherein the seal member comprises a valve adapted to inflate an interior region of the seal member with a fluid. 
     
     
         41 . A method of sealing a cylinder having a reciprocating piston disposed therein, the method comprising:
 providing a seal member comprising a first end portion, a second end portion, and an intermediate portion, the seal member having a rib circumferentially disposed at the intermediate portion;   attaching the first and second end portions of the seal member to one of the cylinder and the piston; and   attaching the rib of the seal member to the other of the cylinder and the piston at a mating groove defined in a wall of the other.   
     
     
         42 . The method of  claim 41 , wherein the first end portion comprises a rod forming a bead and wherein the first end portion is attached to the cylinder by clamping the bead thereto. 
     
     
         43 . The method of  claim 42 , further comprising disposing the rod within a folded-over edge of the first end portion of the seal member. 
     
     
         44 . The method of  claim 42 , wherein the second end portion comprises a second rod forming a second bead and wherein the second end portion is attached to the cylinder by clamping the second bead thereto. 
     
     
         45 . The method of  claim 41 , wherein the seal member comprises a flexible sheet adapted to roll upon itself in a direction parallel to a direction of movement of the piston. 
     
     
         46 . The method of  claim 41 , wherein the seal member comprises a cylindrical sheet disposed around an outer diameter of the piston. 
     
     
         47 . The method of  claim 41 , wherein the seal member comprises a plurality of reinforcement members embedded in a flexible rubber material. 
     
     
         48 . The method of  claim 41 , further comprising defining a seal interior region for receiving a fluid by attaching the seal member to the piston and the cylinder. 
     
     
         49 . The method of  claim 48 , further comprising receiving pressurized fluid into the seal interior region. 
     
     
         50 . The method of  claim 41 , wherein the seal member comprises a valve, the method further comprising inflating an interior region of the seal member with a fluid using the valve.