A CANNULA OF CHANGEABLE LENGTH AND SHAPE

摘要

A cannula of changing length and shape, built up of bands linked with each other, which after the end of the cannula separate from each other and immediately after the place of separation, they are folded and inserted into the interior of the cannula, in which they can slide freely toward its beginning or its end. An adjusting device with guiding lamellas is located at the cannula end, the separated sections of the bands pace along the spaces between the lamellas. The elongation of the cannula is effected by pulling and sliding the free parts of the bands by the adjusting device, their arrangement between the guiding lamellas and their pressing and linking in the way predetermined by the location of the lamellas and their fixing in this position are effected by magnetic forces or by meshing the male part and the female part of the bands. The shortening of the cannula is effected by pulling the free parts of the bands toward the beginning of the cannula and the destruction of the cannula from its end.