公开(公告)号：US5211393A

公开(公告)日：1993-05-18

申请号：US777652

申请日：1991-10-16

申请人： Merlan Rolffs ,  Dennis H. Steenhoek ,  Dennis E. Brand

发明人： Merlan Rolffs ,  Dennis H. Steenhoek ,  Dennis E. Brand

IPC分类号： A63B63/08

CPC分类号： A63B63/083 ,  A63B2208/12 ,  A63B2225/093

摘要： A backboard arm is pivotally mounted to a mast member rearwardly offset from the ground supported mast member in which a jack is internally positioned for extending upwardly out of the upper end for engagement with the backboard arm extending over and outwardly thereof. The jack operates in compression and is substantially concealed from sight.

摘要翻译： 背板臂可枢转地安装到桅杆构件上，该桅杆构件从地面支撑的桅杆构件向后偏移，在桅杆构件中，千斤顶在内部定位用于从上端向上延伸，用于与向上延伸并向外延伸的背板臂接合。 千斤顶在压缩状态下工作，并且基本上被遮蔽。