The apparatus includes a stand plate (5) suspended swinging from a frame with two swing planes coupled together. The stand plate (5) is supported by swing units comprising stationary spring bar elements (15) coupled to elastic elements (11) hanging from the frame (1). The elastic elements can comprise one or more interconnected swing metal blocks (6) suspended from the frame by a holder (4). The spring bars (16) engage at the ends in guide holders (17).
