Taras V. Improved accuracy of longitudinal wood sawing on circular sawmills

The object of the research is a circular saw benchof positional type for rip-sawing. The objective of the work is to improve the accuracy and reduce the energy intensity of the rip-sawingprocess on positional type circular saw benchesby improving the design of the benchand the saw. Research method. The manufacturing accuracyof the bench has been investigated in the thesis paper based on the complex approach and the method of mathematical simulation. The methods of solid-state modeling and finite elements have been used to study the operational rigidity of the circular saw. The components of the cutting forces during rip-sawing have been determined on the basis of the basic provisions of the theory of wood cutting. Experimental studies have been performed using the methods of mathematical statistics and experimental design with many factors. Recording and processing of experimental research results has been done using GoldWave harmonic signal editing tool and applications: processing of the experimentalresults according to B-plan "KoefRR7.0"; manufacturing accuracyof the bench "TTV"; statistical analysis of experimental data "Stat"; studyingthe cutting modes on woodworking machines "K31"; regression analysis "REGRES". Scientific novelty.A mathematical model of the accuracy of sawing on acircular saw benchof positional type has been developed for the first time. It enables to describe the nature of the impact of the main factors on the accuracy of sawing and to determine the rational modes of their work by theaccuracy of sawing. The method of combining the toothing rim with the alternation of the teeth with straight and oblique sharpened carbide plates for their functional separation into the slitting and trimming ones has been developed, which allows ensuring the straightness of the cutting and the durability of the tool in the kerf, as well as reducing the cutting power. The system of the workpiece locating on the feeding carriage has been developed, which made it possible to eliminate the errors caused by the moving dynamic system - the sawing saddle,and to ensure an increase in the accuracy of rip-sawing of sawn timber. Regressionaldependencies to determine the accuracy of sawing and the power of cutting with saws with combined toothing rimhave been obtained, depending on the feed rate, the height of the kerf and timber species, which allows predicting the accuracy of sawing and setreasonable modesaccording to the accuracy of treatment. Practical value of the results obtained. The application of the thesis results allows increasing the accuracy of rip-sawing and reducing energy consumption during the manufacture of bar details on a circular saw benchof positional type. The developed system of indicators for estimating the geometrical accuracy of the positional type circular saw benches enables to determine the actual class of accuracy of the machines during the period of their use. The design of the circular saw bench with a positional location of the workpiece on the feeder carriage provides for an increased accuracy of rip-sawing of sawn timber, and the design of a circular saw with a combined toothing rimprovides for an increased accuracy and reduced energy consumption of the process. Industry: Woodworking.