A moving mechanism (M) including a rectangular-shaped structure (S) defined by side members means (CL, L1, L2) parallel to each other and plate-like means (CP, D1, D2) transversally arranged in relation to said side members (L1, L2); a transversal element (T) being arranged between said side members means (CL, L1, L2) and movable along a cylindric guide (CG) parallel to the side members means (C1, L1, L2) between a first position (P1) and a second position (P2); said transversal element (T) including arm-like means (CB, B1, B2) fixed to opposing ends of said transversal element (T) to support centred rod-like means (M1, M2), and plate-like means (Z1, Z2) centred to the rod-shaped means (M1, M2).