of safety enclosure 101 is inserted into opening 205 fig3 b and 3d and extends through sleeve joint coupling 200 into vertical frame member 103 a distance that is sufficient to distribute any shearing and or torquing forces that may be imparted to vertical pole member 105 along the inside of vertical frame member 103 so that vertical frame member 103 does not fail vertical pole member 105 can be secured in vertical frame member 103 using for example a pin 301 and a cotter ring not shown alternatively vertical pole member 105 is secured in vertical frame member 103 using a sheet metal screw and or a bolt and nut fig4 a 4c respectively show a side view a top view and an end view of a second exemplary embodiment of a sleeve joint coupling 400 for a trampoline frame according to the present invention sleeve joint coupling 400 is generally shaped as a u201c t u201d and includes three arm members 401 403 each having a generally round cross sectional shape each arm member 401 403 receives a trampoline frame member not shown in fig4 a 4c of similar cross sectional shape into an opening 404 fig4 c sleeve joint coupling 400 includes an opening 405 shown in fig4 b that receives a safety enclosure vertical pole member not shown in fig4 a 4c having a generally round cross sectional member fig5 a 5c respectively show a side view a top view and an end view of a third exemplary embodiment of a sleeve joint coupling 500 for a trampoline frame according to the present invention sleeve joint coupling 500 is generally shaped as a u201c t.