USING A TWO-MASS FLYWHEEL ON DRIVE SEWING MACHINES

In the drive of modern machines depending on the engine used, driven mechanisms, frequency and magnitude of transient processes, vibrations with varying frequency and amplitude occur. In most cases, they are unacceptable, result in damage to the machine's component mechanisms, need for repair, worsen operating conditions. One of the ways to reduce harmful vibrations from the drive of the machine is by using screw-spring systems in the design of clutches, dual-mass flywheels and more. In machine-building constructions, the springs can be operated either individually or as components of spring loaded systems with a common load. Thus, for a given load, a desired value of the deformation, stiffness or a special, e.g. broken or non-linear characteristic can be achieved. There are two main ways of connecting springs to systems - parallel (with the same or different lengths) and consistently, combinations of these modes are possible. In many cases, the screw springs are required to withstand very high loads, this leads to larger dimensions of the spring and therefore incompatibility with the dimensions of the assembled node. In these cases, parallel (multi-directional) cylindrical screw springs are used, in this way load and small size requirements are provided. The springs are located one at the other, and in order to remove the twisting of the end supports, they are in a different direction of the turns. The load is absorbed by all the springs and distributed proportionally according to their stiffness. Upon deformation of the spring, potential deformation energy is accumulated, but can’t be fully returned to the mechanical system. Losses in a cycle of loading and unloading of the spring determine its absorbing (damping) capability, which is important for spring buffers and vibro-insulators. With properly selected and dimensioned spring systems, the large torsional vibrations generated by the engine are largely neutralized, which protects the machine's mechanisms against damage, prolongs the period of operation, improves operating comfort. The proposed method is to determine the basic parameters of a system of springs in the form of a dual-mass flywheel. The flywheel can be successfully used to reduce the harmful impact of vibrations when driving sewing machines directly.