Gas strut assembly with an internal detent module

Abstract

A gas strut assembly includes a housing defining an interior space. A rod is coupled to the housing, and is slideably moveable between an extended position and a retracted position. A flexible member is secured in position relative to the housing. A rigid member is coupled to and moveable with the rod. The flexible member includes at least one displaceable portion that moves radially away from the central axis in response to a first radial force component of an opening force when engaged by the rigid member moving from the refracted position into the extended position. The displaceable portion moves radially away from the central axis in response to a second radial force component of a closing force when engaged by the rigid member moving from the extended position into the retracted position. The second radial force component is greater than the first radial force component.

1 . A gas strut assembly comprising:
 a housing including a wall extending along a central axis and defining an interior space;   a rod coupled to the housing and slideably moveable within the interior space and along the central axis between an extended position and a retracted position;   a flexible member secured in position relative to the housing; and   a rigid member coupled to and moveable with the rod;   wherein the flexible member includes at least one displaceable portion configured for moving radially away from the central axis in response to a first radial force component of an opening force when engaged by the rigid member moving from the retracted position into the extended position;   wherein the at least one displaceable portion is configured for moving radially away from the central axis in response to a second radial force component of a closing force when engaged by the rigid member moving from the extended position into the retracted position; and   wherein the second radial force component is greater than the first radial force component.   
     
     
         2 . A gas strut assembly as set forth in  claim 1  wherein the rigid member includes a body disposed about and concentric with the rod, and a detent extending radially away from the body and the central axis, wherein the detent includes a first cam surface for engaging the displaceable portion when moving from the retracted position into the extended position, and wherein the detent includes a second cam surface for engaging the displaceable portion when moving from the extended position into the retracted position. 
     
     
         3 . A gas strut assembly as set forth in  claim 2  wherein the flexible member includes an annular base, with the displaceable portion extending axially along the central axis from the annular base. 
     
     
         4 . A gas strut assembly as set forth in  claim 3  wherein the displaceable portion includes a first leg portion having a radially inner surface for engaging the first cam surface of the detent. 
     
     
         5 . A gas strut assembly as set forth in  claim 4  wherein the radial inner surface of the first leg portion is angled relative to the central axis, wherein the first cam surface engages the radial inner surface of the first leg portion at a first engagement angle relative to the central axis such that a force applied axially to the rod along the central axis generates a radial component force thereof directed perpendicularly away from the central axis. 
     
     
         6 . A gas strut assembly as set forth in  claim 5  wherein the first engagement angle is between the range of 0° and 45°. 
     
     
         7 . A gas strut assembly as set forth in  claim 4  wherein the displaceable portion includes a wall portion extending from an axial end of the first leg portion and radially away from the central axis, wherein the wall portion includes an axial end surface for engaging the second cam surface of the detent. 
     
     
         8 . A gas strut assembly as set forth in  claim 7  wherein the axial end surface of the wall portion is angled relative to the central axis, wherein the second cam surface engages the axial end surface of the wall portion at a second engagement angle relative to the central axis such that a force applied axially to the rod along the central axis generates a radial component force thereof directed perpendicularly away from the central axis. 
     
     
         9 . A gas strut assembly as set forth in  claim 8  wherein the second engagement angle is between the range of 0° and 45°. 
     
     
         10 . A gas strut assembly as set forth in  claim 7  wherein the displaceable portion includes a second leg portion extending from the wall portion axially along the central axis and away form the first leg portion, and wherein the second leg portion includes an inner surface for engaging a radial outer surface of the detent to limit radial movement of the displaceable portion inward toward the central axis when the rod is in the extended position to ensure proper engagement between the second cam surface and the axial end surface of the wall portion. 
     
     
         11 . A gas strut assembly as set forth in  claim 1  wherein the at least one displaceable portion includes a plurality of displaceable portions radially spaced about the central axis. 
     
     
         12 . A gas strut assembly as set forth in  claim 11  further comprising a band disposed radially about and encircling the plurality of displaceable portions. 
     
     
         13 . A gas strut assembly as set forth in  claim 11  wherein the band includes and is manufactured from a material having a resistance to expansion that is variable with temperature. 
     
     
         14 . A gas strut assembly as set forth in  claim 13  wherein the band includes a resistance to expansion that increases with a decrease in temperature. 
     
     
         15 . A gas strut assembly as set forth in  claim 14  wherein the band includes and is manufactured from one of a thermoplastic elastomer or a thermoplastic rubber. 
     
     
         16 . A gas strut assembly as set forth in  claim 1  wherein the flexible member includes and is manufactured from a polymer. 
     
     
         17 . A gas strut assembly comprising:
 a housing including a wall extending along a central axis and defining an interior space;   a rod coupled to the housing and slideably moveable within the interior space and along the central axis between an extended position and a retracted position; and   an internal detent module interconnecting the housing and the rod, the internal detent module including:
 a rigid member coupled to and moveable with the rod, and including a body having a detent extending radially away from the body and the central axis, wherein the detent defines a first cam surface and a second cam surface; 
 a flexible member secured in position relative to the housing, and including a plurality of displaceable portions, with each of the displaceable portions including a first leg portion having a radially inner surface, and a wall portion having an axial end surface; 
 wherein the radial inner surfaces of the first leg portions of the displaceable portions are angled relative to the central axis to engage the first cam surface of the detent at a first engagement angle relative to the central axis when moving from the retracted position into the extended position, such that the first engagement angle directs a portion of an opening force applied axially to the rod along the central axis perpendicularly away from the central axis to define a first radial force component of the opening force; 
 wherein the axial end surfaces of the wall portions are angled relative to the central axis to engage the second cam surface of the detent at a second engagement angle relative to the central axis when moving from the extended position into the retracted position, such that the second engagement angle directs a portion of a closing force applied axially to the rod along the central axis perpendicularly away from the central axis to define a second radial force component of the closing force; and 
 wherein the second radial force component of the closing force is greater than the first radial force component of the opening force such that the closing force must be greater than the axial force to displace the plurality of displaceable portions and move the rod from the extended position into the retracted position. 
   
     
     
         18 . A gas strut assembly as set forth in  claim 17  further comprising a band disposed radially about and encircling the plurality of displaceable portions. 
     
     
         19 . A gas strut assembly as set forth in  claim 18  wherein the band includes and is manufactured from a material having a resistance to expansion that increases with a decrease in temperature. 
     
     
         20 . A gas strut assembly as set forth in  claim 17  wherein each of the displaceable portions includes a second leg portion extending from the wall portion axially along the central axis and away from the first leg portion, and wherein the second leg portion includes an inner surface for engaging a radial outer surface of the detent to limit radial movement of each of the displaceable portions inward toward the central axis when the rod is in the extended position to ensure proper engagement between the second cam surface and the axial end surface of the wall portion.