In the paper, the authors discuss the possibility to apply the "Nodalised Beam" method for vibroinsulation of manually operated tools. They indicate the difficulties in applying the original method for this purpose. On the bases of the reciprocity principle, the authors propose a method for modifying the system that allows them to avoid the mentioned disadvantages. Equations derived for the modified system that makes it possible to define the position of nodal points. The relations were verified at a test station. Furthermore, a method of tuning the system was proposed.

The problem of transmitting vibrations with audible frequencies by steel springs, constituting the vibration isolation system was considered in this paper. The analytical relationships allowing determining the value of the transmissibility for the springs resonance frequencies responsible for the transmissibility of high frequency vibrations have been derived and checked by means of FEM method. Also the occurrence of the increasing stresses in the springs in the areas between the resonances has been shown. The typical system, i.e. the serial system with rubber cushion, has been analyzed, reducing the transmission of high frequency vibrations by the spring. It has been shown that the transmission is reduced not as a result of differences in the wave impedance of the boundary of both media but due to the increased dispersion of energy in the rubber, and the analytical relationships allowing the evaluation of the effectiveness of this method have been derived.