Mathematical experiment for determining the magnetic core thickness of a new material feeding mechanism for a sewing machine

Abstract

Purpose. To establish the patterns of influence of geometric and physical parameters of a newly developed material feeding mechanism for a sewing machine on the magnitude of the magnetic force in the working gap, and to determine rational parameters of its magnetic core in order to minimize the mass of moving elements and improve the dynamic characteristics of the device. Methodology. The study was carried out using methods of mathematical modeling and a full factorial experiment. The FEMM (Finite Element Method Magnetics) software environment was used to analyze the operation of the magnetic material feeding mechanism. Results. The influence of the design parameters of the sewing machine material movement mechanism on the magnitude of the magnetic clamping force was determined. It was shown that changing the geometric characteristics of the elements of the upper transporting body, in particular the height of the magnetic core, significantly affects the magnitude of the clamping force when moving the material. It was established that at certain values of the design parameters the system enters a saturation mode, in which further changing the dimensions of individual elements does not lead to a significant increase in work efficiency, which is important from the point of view of rational design and reducing the mass and dimensions of the mechanism. Scientific novelty. For the first time, the influence patterns of the geometric parameters of the magnetic core and the characteristics of the magnetic system on the force in the working gap of the new sewing machine material feeding mechanism have been established. Nomograms have been developed to determine rational parameter values that ensure improved dynamic characteristics and reduced mass of moving elements. Practical significance. The proposed approaches to determining rational parameters of the magnetic core make it possible to reduce the mass of moving elements and improve the dynamic characteristics of the sewing machine material feeding mechanism. The developed regression model, as well as the obtained nomograms and selection tables, can be used by engineers to determine rational design parameters of the device without performing complex mathematical calculations. This ensures a reduction in design time and increases the efficiency of developing new technical solutions.