| 摘要 |
PURPOSE: To make heavy-load support possible by providing a strut extending between inner and outer concentric supports with a first web extending between the base and the tip and a second web crossing the first web nearly at a right angle. CONSTITUTION: A plurality of struts 24 are extendedly provided between inner and outer concentric supports 14, 16. In the strut 24, main axis web 34 extending from the tip of the strut 24 to the base and follower web 50 which extends from the tip to the base on both lateral faces of the main axis web 34 and which is nearly perpendicular to the main axis web 34, are provided. Thereby, rigidity of the struts is enhanced and a heavy load can be supported. |
