The present invention relates to a link device for connecting two parts together, the link device being deformable in substantially one direction only. The device comprises: two substantially identical elastically deformable plates, each plate having two opposite ends; and two spacer-forming elements for interconnecting the corresponding ends of the two plates and for keeping the plates substantially parallel when at rest, no other mechanical link existing between the two plates, and each part being suitable for being fastened to a respective one of the plates; whereby the two parts may be subjected to significant relative displacement along the direction orthogonal to the two plates while relative displacements between them are very limited along the other two directions of a Cartesian frame of reference.