Unidirectional tension rod mechanism

A tension rod mechanism for a tension rod having a first outer shaft and a second inner shaft slideably received by the first outer shaft and rotatable about a longitudinal axis of the tension rod, the tension rod mechanism comprising:

• a unidirectional slip-lock configured to be received in the first outer shaft for rotational movement therewith and unidirectional slidable axial movement relative thereto, the unidirectional slip-lock having a first attachment shaft terminated by a first end flange at one end and a center flange at another end spaced from the one end;
• a threaded shaft fixedly connected to the unidirectional slip-lock by the center flange;
• and
• a collar threadingly engaged with the threaded shaft and configured to be fixedly received in the second inner shaft for movement therewith,
• wherein, when the unidirectional slip-lock is in the first outer shaft and the collar is fixedly received in the second inner shaft, slidable axial movement of the unidirectional slip-lock relative to the first outer shaft may occur only in an expansion direction and a rotation of the first outer shaft relative to the second inner shaft increases the axial distance between the unidirectional slip-lock and the collar.