Problem to be solved: to automatically lock the support member supporting the side fence at a predetermined position.Solution: a pair of arm members 42, one end of which is pivotally connected to a pair of first connecting members provided at predetermined intervals, and a pair of arm membersA pair of second coupling members 43, one end of which is pivotally connected to the other end of the arm member, andA support member 44 detachably supports a side fence having the other end of the second coupling member coupled at a predetermined interval to the sideAn unused position which is provided at the connection portion between the arm member and the second connecting member and approaches the support member to the side edge of the bed frameOr, when a pair of arm members are rotated by moving a side fence to an used position away from the side portion of the bed frameThe arm member is rotated by a predetermined angle relative to the second coupling memberA stopper means 51 for locking the arm member in an unrotatable manner is provided.Diagram【課題】側柵を支持する支持部材を所定の位置で自動的に移動不能にロックできるようにすること。【解決手段】所定間隔で設けられた一対の第１の連結部材にそれぞれ一端が回動可能に連結された一対のアーム部材４２と、アーム部材の他端にそれぞれ一端が回動可能に連結された一対の第２の連結部材４３と、第２の連結部材の他端が側面に所定間隔で連結された側柵を着脱可能に支持する支持部材４４と、アーム部材と第２の連結部材との連結部分に設けられ支持部材をベッドフレームの側辺部に接近する不使用位置、或いはベッドフレームの側辺部から離れる使用位置にそれぞれ側柵を移動させて一対のアーム部材を回動させたとき、第２の連結部材に対してアーム部材が所定角度回動することで、アーム部材を回動不能にロックするストッパ手段５１を具備する。【選択図】図５
