Length-adjustable support device

A length adjustable support device, comprising

• a first rod,
• a second rod,
• a bearing formed on the first rod for axially movably mounting the second rod on the first rod such that the second rod is movable in a translational motion relative to the first rod,
• a movable fastening element for interlockingly axially fastening the movable second rod to the first rod by interlockingly fastening the fastening element to a mating interlocking-connection element,
• the mating interlocking-connection element for the interlocking connection to the fastening element,
• wherein
• the length-adjustable support device comprises a mechanism and, because of the mechanism, the axial translation motion of the second rod causes an additional rotational motion of the second rod, the second rod thus being movable between a first rotational position and a second rotational position relative to the first rod by means of the axial translation motion of the second rod, the fastening element and the mating interlocking-connection element being in mechanical contact with each other in the first rotational position and the mechanical contact between the fastening element and the mating interlocking-connection element being released in the second rotational position and
• wherein the fastening element is designed as a locking lug or a locking pin and teeth are formed on the mating interlocking-connection element for the interlocking connection of the teeth to the fastening element and the teeth are formed as locking elements.