No abstract

The cutting power value, the surface quality of the machined surfaces, and the cutting edge wear were determined in the planar milling of oak wood (Quercus robur L.). The experimental tool was a milling head with two interchangeable blades. The basic material of the three milling cutters was HS 18-0-2-5 high-speed steel (ISO 4957 2018). Two milling blades were treated with different coatings: a multilayer AlTiCrN coating of thickness 1 μm to 4 μm (knife B) and a multilayer MoC coating of thickness 1 μm (knife C). Parameters for the experiment were as follows: tool angular geometry: α = 30°, β = 45°, γ = 15°, and δ = 75°; spindle speed: 3000 min-1, 4000 min-1, and 5000 min-1; feed rate: 6 m/min, 8 m/min, 10 m/min, 12 m/min, and 14 m/min; cutting depth: 1 mm and 2 mm. The results showed that the cutting power for face milling increased with milling length for all three blades. The greatest power was measured at milling using the knife C (mean value of 209.3 W). The wedge wear parameter WBW increased with milling length; knife C reached the greatest value (WBW = 54.0 μm at length of 270 m). The surface quality parameter (Ra) of the machined surfaces was almost unchanged with increasing milling length beyond 90 m for all knives.

Optimal cutting conditions, which lead to a high quality of the machined surface and low energy consumption, are crucial for wood processing. This paper describes the effect of feed speed, cutting speed and mean chip thickness on energy consumption and saw blade surface temperature during the spruce (Picea excelsa) cutting process. In the experiment, the energy consumption and the surface temperature of the saw blades were measured to find the optimal cutting conditions for the energy-efficient cutting process. The surface temperature of the circular saw blade was monitored online using a non-contact infrared sensor connected directly to a PC via a USB connector. The results show that the cutting power and the surface temperature of the circular saw blade increased with increasing feed speed. The lowest values of cutting power were shown by the saw blade CSB3. Compared to the classic CSB1 circular saw blade, the values were lower by 8%. The surface temperature of the circular saw blade is highest at the outer edge (area of the heel of the teeth), and decreases towards the center of the circular saw blade. For an identical mean chip thickness, energy-efficient cutting was achieved at a feed speed of 21 m/min. There must be a trade-off between machine productivity and energy consumption. Monitoring the cutting process of circular saws using intelligent sensors is the way to adaptive control systems that ensure higher quality of the machined surface and cost-effective machining.

The paper presents the experimental results of a research aimed at the distribution of the temperature on the circular saw blade body. The temperature was measured at two distances from the centre of the circular saw blade body (70 mm, 140 mm) by means of an infrared thermometer. Two circular saw blades with the diameter of 350 mm and a variable adjustment of the body (with slots and without the coating, with both slots and coating) were used for the longitudinal sawing of the spruce wood (Picea excelsa) with the thickness of h = 37 mm. Feed speeds ware vf1 = 14 mpm, vf2 = 17 mpm and vf3 = 20 mpm. Cutting revolutions n = 4100 /min. were constant. The measured temperature was in the range from 21 °C till 27 °C. The highest measured temperatures were recorded on the circular saw blade with the slots and coating.

The article is aimed on the possibility of fuzzy control of an experimental device that represents the simplified model of automobile steering booster. The main part of model consists of a graphical unit illustrating the control of speed and supporting torque. Based on the structure of fuzzy controller, various counts and configurations of fuzzy sets were defined, whereby the relevant results were achieved by their application on controlled system.