| 摘要 |
A tube system for tubular constructions consists of mutually linkable tubes (12, 12', 13, 14, 39) and nodal elements ( 15, 19, 23, 28, 31, 35) slippable on the tubes so as to interconnect them. The tubes and the nodal elements are provided on the inner and/or outer surfaces of the free tube ends or free ends of the arms of the nodal elements with at least one circumferential wedging profile shaped on the one hand as a cam (5) which radially projects over an imaginary cylindrical surface (4) and on the other hand as a number of grooves (8) corresponding to the number of cams which radially deepen an imaginary cylindrical surface (7). The wedging surfaces (6, 9) of the wedging profiles substantially follow the course of a logarithmic spiral with respect to the axis (11) of the tubes or nodal elements. The slope of cooperating wedging surfaces has the same value and is so flat that when a determinable relative displacement between the tubes or the tubes and the nodal elements takes place, and the cooperating wedging surfaces contact each other, a joining pressure builds up, creating a clearance free, self-locking frictional engagement independent of direction of rotation and of stress, in the radial and axial directions, between the tubes or the tubes and the nodal elements. |
