Force control strut

Abstract

A force control strut including a housing having first and second ends and an internal chamber, a rod member having an inner end reciprocally movable inside the housing and along the internal chamber, a guide member allowing reciprocation of the rod member in the housing, a bottom portion fixed in the internal chamber, a guide piston secured to an inner end of the rod and slidable along an inner surface of the internal chamber, a first coil spring positioned between the guide piston and one end of the housing to bias the rod member in a given direction in the housing, a first external connector fixed to the rod member, a second connector fixed to the bottom portion, and a damper that includes a plunger reciprocally mounted in a force controlling passageway inside the rod member and movable in a passageway of the rod member.

1 - 38 . (canceled) 
   
   
       39 . A force control strut comprising an elongated housing having an axis and axially opposite first and second ends and an internal chamber with an inner surface, a rod member coaxial with said axis and having an inner end reciprocally movable inside said housing and along said internal chamber and an outer end extending outwardly of said first end of said housing, a top end portion secured at or near said first end of said housing to allow reciprocation of said rod member axially in said housing between a retracted position and an extended position relative to said housing, a bottom end portion positioned at or near said second end of said housing, a guide piston secured at or near said inner end of said rod member and slidable along said inner surface of said internal chamber, a first coil spring positioned between said guide piston and said bottom end portion to bias said rod member in said extended position in said housing or positioned between said guide piston and said top end portion to bias said rod member in said retracted position in said housing, a first external connector fixed at or near said outer end of said rod member, a second connector fixed at or near said bottom end portion, and a damper combined with said rod member, said damper including a plunger having first and seconds ends and a plunger piston fixed at or near said first end of said plunger, said plunger piston and said first end of said plunger reciprocally mounted in an elongated force controlling passageway inside said rod member and coaxial with said rod member, said plunger piston movable in said passageway of said rod member between a compressed and uncompressed position, said second end of said plunger connected to said bottom end portion to force said plunger piston to move in said passageway toward said compressed position to at least partially dampen movement of said rod member in said housing as said rod member moves toward said bottom plug, said second end of said plunger connected to said bottom end portion to force said plunger piston to move in said passageway toward said uncompressed position to at least partially dampen movement of said rod member in said housing as said rod member moves away from said bottom end portion, said plunger piston including a first orifice to allow fluid flow in at least one direction through said first orifice when said plunger piston moves in said force controlling passageway inside said rod member. 
   
   
       40 . The force control strut as defined in  claim 39 , wherein said first coil spring is positioned between said guide piston and said bottom end portion. 
   
   
       41 . The force control strut as defined in  claim 39 , wherein said first coil spring is positioned between said guide piston and said top end portion. 
   
   
       42 . The force control strut as defined in  claim 39 , including a second coil spring, said second coil spring having a different coefficient of compression than said first coil spring, said second coil spring wrapped in a direction opposite to said first coil spring, or combinations thereof. 
   
   
       43 . The force control strut as defined in  claim 42 , wherein said second coil spring is concentric with said first coil spring and positioned adjacently to said first coil spring. 
   
   
       44 . The force control strut as defined in  claim 39 , wherein said orifice includes a valve. 
   
   
       45 . The force control strut as defined in  claim 39 , wherein said plunger piston allows fluid to flow at a different rate through said plunger piston when said plunger piston moves to said compressed positioned than when said plunger piston moves to said uncompressed position. 
   
   
       46 . The force control strut as defined in  claim 39 , wherein said plunger piston includes a second orifices to allow fluid flow in at least one direction through said when said plunger piston moves in said elongated force controlling passageway inside said rod member, said first orifice allowing fluid flow at a different rate through said first orifice than said second orifice when said plunger piston moves to said compressed positioned, when said plunger piston moves to said uncompressed position, or combinations thereof. 
   
   
       47 . The force control strut as defined in  claim 46 , wherein said first orifice includes a valve and said second orifice does not include a valve. 
   
   
       49 . The force control strut as defined in  claim 39 , wherein said elongated force controlling passageway inside said rod member does not include a mechanical spring acting on said plunger piston. 
   
   
       50 . A force control strut consisting of a single elongated housing having an axis and axially opposite first and second ends and an internal chamber with an inner surface, a single rod member coaxial with said axis and having an inner end reciprocally movable inside said housing and along said internal chamber and an outer end extending outwardly of said first end of said housing, a top end portion secured at or near said first end of said single elongated housing to allow reciprocation of said single rod member axially in said single elongated housing between a retracted position and an extended position relative to said housing, a bottom end portion positioned at or near said second end of said single elongated housing, a guide piston secured at or near said inner end of said single rod member and slidable along said inner surface of said internal chamber, a first coil spring positioned between said guide piston and said bottom end portion to bias said single rod member in said extended position in said single elongated housing or positioned between said guide piston and said top end portion to bias said single rod member in said retracted position in said single elongated housing, a first external connector fixed at or near said outer end of said single rod member, a second connector fixed at or near said bottom end portion, and a damper combined with said single rod member, said damper including a plunger having first and seconds ends and a plunger piston fixed at or near said first end of said plunger, said plunger piston and said first end of said plunger reciprocally mounted in an elongated force controlling passageway inside said single rod member and coaxial with said rod member, said plunger piston movable in said passageway of said single rod member between a compressed and uncompressed position, said second end of said plunger connected to said bottom end portion to force said plunger piston to move in said passageway toward said compressed position to at least partially dampen movement of said single rod member in said single elongated housing as said single rod member moves toward said bottom plug, said second end of said plunger connected to said bottom end portion to force said plunger piston to move in said passageway toward said uncompressed position to at least partially dampen movement of said single rod member in said single elongated housing as said rod member moves away from said bottom end portion, said plunger piston including a first orifice to allow fluid flow in at least one direction through said first orifice when said plunger piston moves in said force controlling passageway inside said single rod member, said plunger piston allowing fluid to flow at a different rate through said plunger piston when said plunger piston moves to said compressed positioned than when said plunger piston moves to said uncompressed position, said elongated force controlling passageway inside said rod member absent a mechanical spring acting on said plunger piston. 
   
   
       51 . The force control strut as defined in  claim 50 , wherein said first coil spring is positioned between said guide piston and said bottom end portion. 
   
   
       52 . The force control strut as defined in  claim 50 , wherein said first coil spring is positioned between said guide piston and said top end portion. 
   
   
       53 . The force control strut as defined in  claim 50 , including a second coil spring, said second coil spring having a different coefficient of compression than said first coil spring, said second coil spring wrapped in a direction opposite to said first coil spring, or combinations thereof. 
   
   
       54 . The force control strut as defined in  claim 53 , wherein said second coil spring is concentric with said first coil spring and positioned adjacently to said first coil spring. 
   
   
       55 . The force control strut as defined in  claim 50 , wherein said orifice includes a valve. 
   
   
       56 . The force control strut as defined in  claim 50 , wherein said plunger piston includes first and second orifices to allow fluid flow in at least one direction through said when said plunger piston moves in said elongated force controlling passageway inside said rod member, said first orifice allowing fluid flow at a different rate through said first orifice than said second orifice when said plunger piston moves to said compressed positioned, when said plunger piston moves to said uncompressed position, or combinations thereof. 
   
   
       57 . The force control strut as defined in  claim 56 , wherein said first orifice includes a valve and said second orifice does not include a valve.