| 摘要 |
<p>A peg, passing through openings in opposite shanks of the U-section post and recess in the cross-member, is used to hold the two together. A wedge is inserted between the end of the cross-member fitting in the post and the inner wall of the latter. The cross-member can have an end extension piece by which it fits into the post, the end face of this piece being concave, while the wedge is of angular section bearing against this concave face and the insides of the post shanks. Specifically the face can be of V-section. The design combines ease of assembly with stiffness once erected.</p> |
