RESOURCE-SAVING SEMI- AUTOMATIC MACHINE WITH ELECTRONIC DIGITAL DEVICE FOR IMPROVEMENT OF THE MACHINE FOR CORD TIGHTENING OF A WORKPIECE WITH A FRICTION

Abstract

The paper considers the proposed improved resource-saving semiautomatic machine with an electronic digital device for friction cord tightening of workpiece from various materials. The productivity of machines and devices for performing technological operations of tightening and forming mainly depends on the unification and possibility of a universal approach to the process.Due to automation and unification of operations of the processes of tightening and forming of parts, it is possible to significantly improve the productivity of equipment for performing forming operations. This can be done by creating a new machine design, taking as a prototype an existing machine for tightening the heel part and improving it with a pilot plant. The result will be equipment that performs a universal process of forming the workpiece as a whole with the additional ability to control the factors that affect the quality of the tightening. Improvement of these indicators will generally lead to a reduction in energy costs and a reduction in the cost of equipment compared to the prototype. The theoretical and experimental studies carried out in previous works and the results obtained have created the prerequisites for the development of fundamental and constructive technological schemes of automated high-precision equipment for high-quality molding based on the friction cord tightening method. Based on the results of experimental studies, a design scheme of a semi-automatic machine with an electronic digital device for cord tightening of a workpiece with a friction band MFSHZ-1 was proposed. The MFSHZ-1 machine has the following actuator designs. The lower support consists of a stand and a bracket. The support is rotated on the axis to the required angle by a hydraulic cylinder.When the support moves to the heel friction frame, it is fixed in this position by a cylinder, the rod of which enters the hole of the bracket fixed to the support. The support is lifted upward by a hydraulic cylinder. The height position of the fitting and the sock-and-bundle frame is adjusted by nuts, and in the longitudinal direction it is fixed on the rail with a dog. The longitudinal movement of the frame is controlled by a hydraulic cylinder and the transverse movement by a hydraulic cylinder. The position of the frames across the track is regulated by earrings. When lubricant is supplied to the rodless cavity of the hydraulic cylinder, the slider moves, and the heel friction frame moves with it until it touches the pad. The crimping width is adjusted with screws. The heel frame is replaceable and is set depending on the type of shoe. Due to the fact that the machine is single-section and the right and left half-pairs of workpieces are processed alternately, the bracket with the friction frame is rotated in one direction or the other by a cylinder. In order to determine the technical and economic performance of the equipment, we conducted a pilot tightening of 5 genuine leather blanks using an improved experimental setup with accurate time measurement (timing) of all elements of operations. Comparison of the technical and economic indicators of the equipment developed in the work and typical tightening equipment showed that the presented equipment can be used quite effectively at shoe enterprises