Abstract: A ball and socket joint for connecting one end of a rail member to a base member includes a ball mounted on the end of the rail member. A socket and a radial slot in the base member permit pivoting of the rail section relative to the base between a first position and a second position. The socket also permits rotation of the ball in the socket to permit rotation of the rail member about its longitudinal axis relative to the base member between a locked orientation and a unlocked orientation. When the rail section is in the locked orientation it cannot pivot relative to the base member and when the rail section is in the unlocked position it is free to pivot relative to the base member.

Abstract: A collapsible playpen having a pair of spaced apart articulated end frames, wherein the end frames are separated by articulated upper and lower rails. The end frames and rails are constructed so that the playpen is collapsed by folding the lower rails to draw lower portions of the end frames together and simultaneously rotating the upper portion of the opposing end frames away from each other such that the distance between the upper portion of the end frames is greater than the distance between the lower portion of the end frames.