Influence of the suspension shape on the dynamic characteristics of the electrodynamic shakers

Electrodynamic shakers are being used for years in dynamic tests of machines and devices. One of the main components of electrodynamic shakers is the armature suspension. Suspension is one of the factors responsible for the dynamic characteristics of the shaker. Various types of suspensions are used in shakers. Their role is to ensure the correct stroke of the armature and to keep the coil concentrically in the magnetic gap. As part of the research, the influence of the shape of the suspension springs of the electrodynamic shaker on its dynamic characteristics was evaluated. During the research, self-designed electrodynamic shaker was used, in which a suspension consisting of two-disc springs made of glass fiber with a thickness of 0.5 mm was used. Eight different spring types were prepared for the study. The tests were carried out in laboratory conditions on a previously prepared test bench. For each of the springs tested, dynamic frequency characteristics were determined for three frequency ranges: 10 – 100 Hz with a step of 10 Hz, 100 Hz – 1000 Hz and 1000 Hz – 10000 Hz with a step of 100 Hz. Studies show a significant influence of the shape of the springs used on the dynamic characteristics of the modal shaker. For the preselected springs, tests were carried out without and with a load. The characteristics determined during the research were analyzed, which allowed to indicate the optimal shape of the spring, due to the values of the generated force and the linearity of the dynamic characteristics.